small sailboat inboard engines

Yachting Monthly

• Digital edition

Best marine diesel engines: a buyer’s guide

• Sam Fortescue
• September 24, 2021

Modern marine diesel engines may look very similar to the large, noisy, oily chunks of iron of yesteryear, but a lot has changed under the bonnet, says Sam Fortescue

An inboard engine is a critical part of any boat, whether you're a purist who only motors when safety demands, or if you'd rather get into harbour in time for last orders. The chances are you also rely on the engine for battery charging. Credit: WorldFoto/Alamy Stock Photo

Best marine diesel engines: the new tech making inboard engines cleaner, more efficient, lighter and more reliable

Once referred to as the ‘auxiliary’ engine , your boat’s inboard diesel is now so much more than just a helping hand.

Not only is it central to your boat’s ability to manoeuvre safely into tight marina berths, it also allows you to keep up average speeds and make the tidal gate before it closes, charges the batteries that run the ever-expanding suite of entertainment and navigational tools aboard, and keeps the beers cold and showers warm.

Despite visual similarities to the noisy models of yesteryear, modern marine diesel engines are cleaner and more efficient, lighter and more reliable. And they are increasingly interactive.

If you’re considering re-powering your boat, here are some of the key features to look out for.

Marine Diesel Engines: Emissions

Tighter regulation in Europe has been forcing engine manufacturers to reduce the harmful emissions generated by their equipment.

In the marine sector, that means complying with the 2013 Recreational Craft Directive, known as RCD 2, and often with the EPA Tier 3 requirements in the USA.

Though most manufacturers anticipate further tightening in the future, there is nothing yet on the cards for marine diesel engines in the leisure sailing sector.

The focus on reducing emissions has resulted in a better understanding of the combustion process inside the cylinder.

A key pollutant, nitrous oxide, is formed at higher combustion temperatures, so one advance has been to reduce those temperatures.

A mechanical system, like this Beta Marine engine, offers ease of maintenance. You don’t need a laptop to reset the electronics

Increasing the swept volume of the cylinder theoretically creates more power, because there is room to burn more fuel each cycle, but if you keep fuel consumption the same, the diesel generates less heat in combustion.

Another area of development has been around the fuel injection system.

A lot has been written about the desirability and reliability of so-called common rail versus mechanical injection for marine diesels.

As Andrew Growcoot, CEO of Beta Marine puts it: ‘The benefits of a mechanical system [are] simplicity and ease of maintenance. One doesn’t need a laptop to reset the electronics ; a mechanical system is safe and will not power down at the wrong time.’

Beta Marine is a British marine diesel engine supplier that uses a Kubota block, and has no intention of introducing the technology any time soon on sub-100hp engines.

The same is true of France’s Nanni and Spain’s Solé, who both supply good, reliable diesel marine engines to the sailing market.

Hedley Beavis of Solé distributor Engines Plus says research to find a common rail injection system has been delayed by COVID-19.

‘It is not an easy task finding a reliable common rail engine but also at a reasonable price for the marine market,’ he adds.

But while common rail injection makes your engine reliant on an electronic control unit for precise high-pressure fuel injection and makes it more susceptible to poor quality fuel, this widely used technology can also offer significant benefits in terms of power and fuel consumption.

Continues below…

Diagnose and fix marine diesel engine problems

Tim Bartlett explains how you can diagnose some common marine diesel engine problems, and fix most of them

White diesel: is it worth converting from red?

Duncan Kent examines the implications of switching from red to white diesel and what you can do to avoid fuel…

How to: troubleshoot your marine diesel fuel system

One of the most common causes of a marine diesel engine not starting is a fuel problem. If you have…

How to avoid diesel bug

Diesel bug can clog filters, wreck engines, corrode fuel tanks, and leave you powerless at sea. Ben Sutcliffe explains how…

Plus, it’s quieter and produces less vibration.

That’s because the diesel is injected as a huge number of tiny droplets, greatly increasing the surface area for better combustion.

Common rail injection is usually found on more powerful engines – Volvo Penta uses the system in its D3 engine and above, which starts at 110hp.

But Yanmar took a bold step in 2018 when it launched a new 40hp unit with electronic fuel injection. The 3JH40 is still the smallest marine diesel engine with this technology.

‘Through common rail technology, the 3JH40 offers minimal fuel consumption and exceptionally low noise and emission levels, exceeding EPA Tier 3 and EU RCD Tier 2 emission regulations for virtually smoke- and odour-free operation,’ says marketing manager Sander Gesink.

‘People don’t want to have the smell of diesel onboard making them seasick.’

The demand for more plentiful electrical power on board boats has led engine manufacturers to increase the output of their alternator systems.

Where a typical alternator on a 30hp engine might have been around 50A two decades ago, they are now often in excess of 100A.

So, for example, even Volvo Penta’s entry-level D1-13 engine packs a meaty 115A alternator with its own built-in charging regulator, for optimal battery charging.

The 50hp D2-50 offers the same alternator, as well as the option of expanding output with a pulley take-off for a second alternator.

Even Volvo Penta’s entry-level D1-13 engine packs a meaty 115-amp alternator with a built-in charging regulator

Beta Marine’s 43hp engine comes with a 70A alternator as standard, but can accommodate upgrades to 120A or 175A alternators, as well as a second 175A alternator for really hefty charging.

It is worth noting, however, that many of these alternators remain fairly basic bits of kit with an inflexible charging regime.

That’s one reason that Yanmar has worked with Mastervolt on its 150hp-plus 4LV engines to develop a secondary charging option in addition to the on-board 130A unit.

Using the Alpha III charge regulator, that alternator will put exactly the right charge into the battery bank on a three-step regime that works regardless of the RPM by varying the field current going into the alternator.

Units on smaller, older marine diesel engines can easily be retrofitted with a regulator, such as Sterling Power’s Pro Reg.

Interactive marine diesel engines

It used to be that marine diesel engines would buzz along in the background unless they overheated, in which case you were treated to an ear-splitting alarm from the control panel.

They still do sport their own dedicated warning lights which ping on if oil pressure drops or the temperature rises above a safe 80-90ºC.

But with the growth of instrumentation on board, and the development of fast, bi-directional networks, engine manufacturers have had to up their game.

That means enabling the engine to put data into your NMEA2000 instrument network about its speed, temperature and oil pressure, as well as many other potential parameters on more complex systems.

‘Captains just want to see their engine performance and details on their MFDs,’ says Yanmar’s Gesink.

Steyr’s unique monoblock marine diesel engine starts at 75hp. The MO 4-CYL uses a two-stage unit injection system with the benefits of high-pressure fuel without the requirement for electronic control

As a common rail injection engine, Yanmar’s 3JH40 already has the electronics necessary to connect directly to the boat’s NMEA2000 instrument network, as well as the VC10 electronic throttles and other controls via a J1939 CAN bus.

These include the YD42 smart panel display, which will toggle through engine data such as load percentage and engine hours, as well as standard navigational data like depth and wind speed.

‘Direct connectivity to NMEA and J1939 CAN-bus networks has been purpose engineered into the 4LV range, allowing future-proofed integration to any multifunction bridge display. Same counts for the 3JH40 and the rest of our common rail engine range,’ adds Gesink.

While 110hp-plus Volvo Penta marine diesel engines – the D3 upwards – have been built since 2006 with a proprietary Electronic Vessel Control system, its smaller D1 and D2 marine diesel engines were given a hybrid solution.

This Mechanical Diesel Interface (MDI) is a black box fitted to the side of the exhaust manifold, where heat and vibration have made it somewhat temperamental.

Without the MDI, the engine simply won’t run, although it is quite straightforward to bypass.

Volvo sells an Easy Connect adapter that plugs into the J1939 socket on the MDI and feeds its data out onto a NMEA 2000 instrument network, allowing it to be visualised on the plotter or other displays.

Volvo’s Easy Connect app allows you to monitor engine-specific data over Bluetooth on smart devices

Other manufacturers also offer products that can do this.

Volvo offers dedicated instruments to show fuel level, temperature and voltage if you want it.

It also produces its own glass bridge touchscreen displays from 7in to 24in, although this will mainly appeal to the powerboat market.

More interesting for sailors is Volvo’s Easy Connect app available for smart devices, which allows you to monitor engine-specific data over Bluetooth thanks to the Easy Connect adapter.

Other engine manufacturers have adopted a more agricultural approach.

Beta Marine, for instance, has worked with market-leading sensor firm Actisense to build a module that plugs into the wiring loom that runs between the engine and the control panel, and feeds data into the NMEA 2000 network.

It only works with one of Beta’s more expensive C and CW Deluxe control panels, and requires a bit of splicing in of wires.

Solé also offers an NMEA 2000 converter to get analogue data from the engine into your digital instrument network.

You still need a dedicated control panel, but the SDC2000 kit even allows the engine’s alarms to be transferred to your MFD.

It is compatible with all Solé diesel engines since 2008.

France’s Nanni uses a similar NMEA adapter, but also offers a dedicated interactive display to enhance its control panel – available for all engines above 21hp.

There is a small 4in model, and larger 7in and 9in display built around Raymarine technology, with charting, radar and CHIRP sonar support.

The choice is yours

Every owner will make up their own mind on common rail injection.

It looks like the way of the future, judging by the automotive sector, but critics point out that poor quality fuel and the need for maintenance in out-of-the-way places weigh in favour of mechanical fuel systems.

It depends whether you’ve got far-flung cruising in mind, or whether you plan to stick to home waters.

Weigh up your priorities. The Yanmar’s fuel consumption is certainly better than the competition.

But the Beta offers one of the best torque curves, equating to more usable power at cruising revs.

Thinking about going electric? Click here

Either way, don’t be tempted to overpower the boat, as marine diesel engines are most efficient at around 80% of their revs.

If you want the engine to feed data onto the network, it’s best to know from the outset, so the engineer can hook the whole thing up.

That said, it’s hardly a complex job, although the necessary kit amounts to several hundred pounds in the aftermarket.

If you’re looking to re-power, the key criteria will always be the space available, and access to filters, impellers and freshwater systems for maintenance .

While there’s broad consensus about hydrogen being the fuel of the future, the path to fuel-cell propulsion is distinctly unclear.

In the meantime, alternative fuels may play an increasing part in the energy mix for combustion engines: methanol or ammonia can be stored as liquids and mixed with diesel in a combustion engine.

There are challenges to overcome, not least the nitrous oxides produced when ammonia burns, but there is research time going into just that.

Shipbuilder CMB is working with manufacturers of bigger engines to make the design tweaks to run on dual fuels; focused on the injection system.

A more immediate possibility is the use of hydrogenated vegetable oil ( HVO ) or gas-to-liquids (GLT).

HVO is essentially biodiesel and can be made from waste cooking oil, while GLT is made from natural gas and is said to burn more cleanly than diesel.

‘The advantage of mechanical injection systems is that the engine can take advantage of using low- emission alternative fuels, such as HVO and GLT, without alterations to the engine,’ adds Beta Marine CEO Andrew Growcoot.

Marine Diesel Engines: A buyer’s guide

Volvo penta d2-50.

Volvo Penta D2-50: Easy to get NMEA data from the engine

Volvo has an odd gap in its engine line-up between the 28hp D1 and the 50hp D2, which exist in both shaft and saildrive formats.

The D2 marine diesel engines run at 3,000rpm, which is pretty standard for this power rating.

In general, slower rotation makes for less noise and vibration. Both series use inline injection and feature the MDI electronic interface which has suffered from reliability problems in the past.

On the plus side, the interface makes it easy to get NMEA data out of the engine and onto your instrument network. It also opens up a good range of snazzy remote displays.

Volvo’s ergonomic electronic controls won’t work with the D2 engine, however. They are only compatible with the EVC marine diesel engines that run on common rail injection.

Volvo has excellent, if expensive, global support.

• Power: 51hp (37.5kW) crankshaft
• Cylinders: 4
• Displacement: 2,200cc
• Fuel consumption at max rpm: 11.5lt/hr
• Dry weight: 249kg
• D2-50: £9,360
• Dealers: www.volspec.co.uk ; www.goldenarrow.co.uk

Yanmar 3JH40

Yanmar 3JH40: An award-winning 40ho engine

With a power output rated at 40hp, this hugely successful, award-winning engine was launched in 2018.

Its key feature is the common rail injection system which Yanmar has introduced with claims that it reduces smoke and odour to nearly nil.

This is due to the more complete combustion of the diesel fuel when injected under high pressure.

It also operates at a relatively low 3,000rpm, which makes it quieter than faster-spinning engines, and reduces vibration.

Yanmar has developed a series of digital controls for its engines. The VC10 and VC20 electronic throttles make data such as engine loading available on the network.

There are also dedicated displays like the YD42, which has a full-colour screen. Otherwise, a £350 analogue-to-digital converter will get your engine data onto the NMEA 2000 network.

There’s a saildrive option, which costs some £2,500 more than the shaft alternative.

Yanmar engines are also very well supported with servicing.

• Power: 40hp (29.4kW)
• Cylinders: 3
• Displacement: 1,642cc
• Fuel consumption at max RPM: 8.8lt/hr
• Dry weight: 192kg
• www.barrus.co.uk

Beta 43: Excellent, mid-range torque for its rating

Beta Marine diesel engines are based on the solid Kubota block, and represent good value, no-frills performance.

Painted a distinctive red colour, they offer flexible installation thanks to a good range of options.

This makes them well suited to repowering in tight corners.

Though the design is constantly being improved, this is a traditional mechanical engine with the minimum of electronic gimmickry.

It offers excellent mid-range torque for its rating.

The standard control panels are steadfastly analogue, although a NMEA2000 converter is available to get limited engine data onto the network.

A new digital display panel is now available, with a standard loom input and a NMEA 2000 output.

Reliable and well supported with spares, and readily serviced, these are good engines that are sold worldwide.

• Power: 43hp
• Displacement: 1,999cc
• Fuel consumption at max RPM: 9.3lt/hr
• Dry weight: 238kg
• www.betamarine.co.uk

Nanni N4.43

Nanni N4.43: Low rpm makes for a quieter unit

Nanni, a French-Italian brand, is well represented in the UK by AR Peachment. These distinctive blue marine diesel engines have helped make Nanni the world’s third largest marine engine supplier.

The engines are fairly traditional, with indirect mechanical fuel injection, natural aspiration and water-cooled exhaust manifold. Relatively low RPM makes for a quieter unit.

The N4.43 is in fact a de-rated version of the larger 50hp unit.

Being a mechanical engine, the N4.43 relies on an NMEA adapter to get engine data onto the network.

Though controls remain analogue, the N4.43 is compatible with a series of Nanni digital displays which start at 4in.

Support at the leisure end is not as widespread as bigger brands, but as it’s based on a Kubota engine block, it should be easy to find a competent mechanic.

• Power: 43hp (29.4kW)
• Displacement: 2,197cc
• Fuel consumption at max RPM: 10.3lt/hr
• Dry weight: 228kg
• www.peachment.co.uk

Solé Mini-44

Solé Mini-44: Decent torque at mid range

Spain’s Solé produces a very wide range of diesel marine engines, and the Mini-44 is aimed at yachts in the 10-12m LOA range.

Sam Fortescue is a freelance marine journalist and former magazine editor who sails a Sadler 34, which has taken his family from the Caribbean to the Baltic

It looks cheaper than the competition, but Solé’s model is to quote a fixed price and not engage in the inevitable discounting of the other brands.

This is the smallest four-cylinder unit the company builds, giving quieter running but greater fuel consumption at top speed.

Though rated 42hp, it has a smaller capacity and has to work harder to achieve it.

For that reason it compares better against 38hp models.

A purely mechanical engine, it relies on cam-driven indirect fuel injection and produces decent if not outstanding torque at the mid range.

Available with an impressive range of gearboxes, including saildrive fittings, the Mini-44 is a very flexible engine with lots of options.

A very expensive converter (SDC2000 – £800) is available to transfer the engine’s analogue data into digital signals for your NMEA 2000 network.

But the control panel options, although very attractively styled, remain resolutely analogue.

Solé has decent global support, naturally focused on Europe and the Spanish-speaking world.

• Power: 42hp (30.9kW)
• Displacement: 1,758cc
• Fuel consumption at max RPM: 10.4lt/hr
• Dry weight: 175kg (w/o gearbox)
• www.enginesplus.co.uk

Enjoyed reading Best marine diesel engines: a buyer’s guide?

A subscription to Yachting Monthly magazine costs around 40% less than the cover price .

Print and digital editions are available through Magazines Direct – where you can also find the latest deals .

YM is packed with information to help you get the most from your time on the water.

• Take your seamanship to the next level with tips, advice and skills from our experts
• Impartial in-depth reviews of the latest yachts and equipment
• Cruising guides to help you reach those dream destinations

Follow us on Facebook , Twitter and Instagram.

6 Great Small Boats With Inboard Motors (With Pictures)

Here are some popular small boats with inboard motors.

Boats with inboard motors are typically bigger boats but there are some cool options out there for small models as well.

Let’s get started!

Table of Contents

Small Fishing Boats with Inboard Motors

Offshore fishing boats are meant for rough waters and are often powered inboard/outboard, outboard, or inboard engines.

This is because they can be both fuel-efficient (you can run out of fuel in the middle of rough waters) but powerful at the same time.

1) Albemarle 32 Express

The 32 Express is one of the best inboard fishing boats out there. It is strong with a:

• Accessible Gel coated Bilge Areas
• Bonded and Mechanically Fastened Hull, Deck, and Liner
• Fiberglass Encapsulated Stringer System
• Heavy Duty Vinyl Rub Rail with Stainless Steel Insert
• Molded, Hand-Laid Solid Fiberglass Construction with Premium Gelcoat Finish and Vinylester Resin

When you’re not fishing, you can relax in the main cabin which has:

• Access to Bilge
• Carpeting Throughout
• Sofa, Converts to Double Berth
• Storage Compartment and Large Drawers below Berth
• Recessed Indirect LED Lighting
• Reverse Cycle Air Conditioning/ Heat System
• Salon Table
• Coast Guard Safety Kit
• Custom Cherry Cabinetry with Satin Finish
• Diagonal Double Berth
• Chrome Finished Positive Catch Push Button Latches on All Cabinetry
• Hanging Locker
• Built-in Upholstered Seating

2) The Supra Comp TS6M

The Supra Comp TS6 was made from 1986-1992. While that might seem like it’s a bit dated, it definitely stands the test of time.

Not only is it a great versatile inboard boat that works well as a runaround as well as a fishing boat, they normally come with a few extra amenities because they have been improved upon by their previous owners.

The TS6M is a great 19-foot fiberglass boat They come with the standard sound system, ski towers, and vinyl upholstery. Often, you will see them for sale with the upholstery updated as well as new paint-jobs. If not, the money you save on buying a used boat can go toward a custom paint job.

Just make sure you consult with a marine specialist when buying a used boat.

Rib Boats with Inboard Motors

Ridged inflatable boats (or Rib boats) are great for fun day trips in freshwater.

Some of the best options for RIB boats are from AB Inflatable.

3) Zodiac MilPro

The Zodiac Milpro line of Rigid Inflatable Boats (or RIB boats) is one of the only RIB boats that offer a single or a double inboard diesel (with water jet) engine. They also offer a sterndrive or surface drive. They are used mostly by the coast guard as well as other professionals who work on the water.

Because they are so well-regarded as tough and hearty, they are often seen as indestructible.

Their tubes are foam filled and D shaped in order to fit their hulls, which are made of aluminum, carbon-reinforced plastic, or glass-reinforced plastic. Their inflatable collars are made of heavy-duty CSM/neoprene, polyurethane-coated fabrics which can withstand so much.

The foam they use is from Zodiac’s own Durarib system.

Aluminum Boats with Inboard Motors

Aluminum boats are great for tooling around, fishing, or just spending some time out on the lake or river.

4) Weldcraft Renegade

If you’re looking for a great aluminum boat with an inboard motor, try the Weldcraft Renegade on for size. This also has an inboard jet, so you can get to your favorite fishing spot quickly.

The Renegade is powered by either a catalyzed 5.7L MEFI-5 with an American Turbine SD-309 inboard pump or a 200HP Optimax Sportjet.

Both of those options will allow for some great fishing, crabbing, cruising, or for some water skiing. It comes in two different models: the Renegade 18 and the Renegade 20.

They both offer a heavy-duty fold down top with:

• Curtains along the side and a backdrop,
• two folding seats on adjustable pedestals,
• bow storage,
• marine-grade plywood floors,
• carpeted sidewalls,
• side storage trays,
• side rod racks,
• and an in-line muffler system.

5) Northwest Boats’ 208 Northstar

The 23’3″ Northwest Boats’ 208 Northstar is also a great option. This one also comes with an inboard jet. It is built to be used and has family-friendly dimensions and maximum versatility. You can take it in white waters or of a leisurely day trip with your family.

With the driver and passenger captain’s seats, side curtains, EX-Arch step-through door, and storage bench seating, it is built for comfort and can go wherever you want to go.

The 208 Northstar also has stainless steel cup holders, rod racks on the gunwale, subfloor storage, bow storage access panel, and vinyl marine-grade plywood floors.

There are a ton of optional features as well, like:

• Hydraulic steering upgrade,
• bow fish box,
• AM/FM CD-Radio,
• wash down pumps for the driver and passenger seats,
• removable transom ski pols and sport seating,
• as well as a bow mount trolling motor wiring Hang, rig and run.

Center Console Boats with Inboard Motors

Boats with center consoles are usually used as workboats. The steering consoles are mounted in the center of the boat. These engines are powerful and can get to places quickly.

6) Dusky 233

This classic center console inboard has been around for a while and you can find them on a few used boat sites. Of course, you can find both inboard and outboard options on boat trader sites. It has an easy-going engine made for the tinkerer.

If you’re the type that likes working on your own boat, the Dusky engine 350 parts are easily found in most part stores (even West Marine). With all the weight riding forward, the ride is smooth and soft. It’s also spacious and has plenty of room off the transom.

The 23′ Dusky 233 inboard has a hull made of fiberglass and is made for skiing and fishing. It comes with:

• The standard rod holders,
• beverage holders,
• bench seats,
• and anchor locker.

They are also available with GPS and plotters, VHF, and compass.

What are the best inboard gasoline engines?

If you have a bit of money to burn and you’re looking to upgrade the inboard engine on your boat, here are some of the best boating engines on the market today.

• The Mercury Mercruiser 3.0 TKS: This is great at powering small pontoons, runabouts, and small commercial fishing boats. It’s good for everything because it is both reliable, has excellent fuel economy, and has a great reputation for being a terrific performer. It has a patented turnkey start (TKS) and has 135 hp.
• The Crusader 6.0: The Crusader is a direct fuel injection inboard motor. Powered by gasoline, it has 375 hp, which is a hefty engine for a mid to small boat.
• The Ilmore MV8 5.7L: The MV8 is a durable, efficient, and reliable recreational inboard engine. The 324.9 hp engine has been certified for tournament use (for and by the American Water Ski Association).

6 types of marine engines

When it comes to picking out boats and engines, there are an array of choices for boaters to choose from. The principle is the same as any other internal combustion engine (like the one found in your truck or car).

Except that, instead of setting wheels in motion, a boat motor turns the propeller, via the drive shaft.

There are six different types of motors including:

Inboard drives.

Otherwise known as an inboard motor, these are engines enclosed in your boat. The rudder, props, and driveshaft are all located under your boat. These are powered by diesel or gasoline and are available in single or twin engines.

The most common type are 4- or 6- cylinder engines. Another option is to have a marine V-drive engine, which is located closer to the stern. Inboard engines are the types of engines we will be focusing on, so I’ll delve deeper into this a little later.

Outboard motors.

This is a motor located on the outside of the boat. It is the most common type among freshwater boats: whether fishing or pleasure craft. They are self-contained and are mounted to the transom (or the rear wall) of the boat.

The mounted unit will contain an engine, steering control, and a propeller. Some even have cables which help pivot the entire motor, to help with steering.

The 2- and 3- cylinder versions are the most common outboard motor but there are some beefy V-6 and V-8 options out there.

Sterndrives (AKA Inboard/Outboard).

Like the outboard motor, these are located outside the boat but is mounted inboard, in front of the transom. Some people say this is the best of both worlds.

It can be pivoted to move up out of the water (like other outboard motors) but it gives the boater more control (like inboard motors). They are also commonly bigger than outboard motors with the most common sizes being 4-cylinder and V-6 engines.

Surface Drives.

These are used by boats that have to perform a lot: speedboats, boats used for racing, etc. They’re also used in large boats due to the fact that the propellers are replaced with jet drives to push the boat through the water. The water is drawn in through a jet under the hull, then flows through impellers, which are hooked up to a nozzle. The nozzle is what steers the boat.

Jet drives accelerate quickly but aren’t the best option when it comes to fuel efficiency, so watch out for that.

Pod Drives.

A pod drive uses a propeller under the engine, which helps pull the boat through the water, instead of being pushed through the water (like with the other engine types). They normally come in pairs, in order to help with maneuvering through the water. This is extremely helpful when it comes to docking the boat or squeezing it through some tight spaces.

How do inboard marine engines work?

An inboard engine is somewhat similar to a car engine. It creates power in the same way and drives the boat the same way a motor powers a car. After all, they are both combustible engines which have cylinders which use fuel. Sparks ignite the fuel (mixed with air) creating an explosion, pushing the pistons into place.

These pistons are connected to crankshafts (otherwise called drive shafts). As the pistons are pushed down, the drive shaft spins, which moves the vehicle.

As far as boats are concerned, the propellers, are connected to the drive shaft. So when the drive shaft spins, so do the propellers.

One main difference between a car engine and an inboard engine is how the inboard engine cools itself.

While cars use radiators, inboard engines use the surrounding water. The water is pumped into the inboard, cools the engine, then is pushed back out with the engine exhaust. This is why you’ll see water coming from the back of a boat with an inboard engine.

Now while they work somewhat similarly, they are not interchangeable. Don’t let anyone convince you to use a car engine for an inboard motor. For one, the inboard motor works a lot harder than a car engine. For example, getting a four-ton boat to power through the water at a decent speed is the same as towing a 24-foot trailer up six percent grade incline for ten miles, using a V-6 engine.

In addition, car engines don’t heat up as much as marine engines do, because they don’t have to work as hard.

How to take care of an inboard marine engine

There are a few ways to take care of your inboard engine:

• Flush your engine regularly
• Prepare for the spring
• Winterize your engine

How do you flush an inboard engine correctly?

Flushing your inboard engine can be a fairly simple process.

There are two main reasons why you would want to flush a marine engine. Both of those reasons are due to avoid future issues with your boat:

• In order to reduce the corrosion from the saltwater.
• As a part of the winterization process, in order to keep the engine block from freezing and cracking.

Running your boat in saltwater means that you’re basically running your boat through a sea of corrosive liquid. However, flushing your inboard engine regularly can keep your important engine parts free of rust and deterioration.

Luckily, most new engines let you hook up a hose into the intake, which means that you can just flush your engine right there. It’s as easy as watering a flower garden.

• Cover the air intake to prevent debris from getting in while you flush it
• Hook up a hose to the water intake, let the water start flowing, then let the engine idle. You’ll know it’s clean when the water running through it, comes out clean.
• Make sure you check the prop shaft (it should turn without any stiffness), stuffing box (no leakage, wear, or tear), water pump impeller (check for rust, cracking, or dry spots), and engine hoses (replace them if they look like they’re starting to crack).
• Open the engine compartment to check for scents. If it’s starting to smell, look around. If you smell fuel, look for a leak in the fuel line, fuel filter, or the tank fitting.

These easy steps ensure that your engine will run smoothly and will prevent bigger problems down the road. It might seem as though you can push these tasks for later. However, waiting too long can lead to engine room flooding, rust, overheating issues, or misalignment.

How do you prepare your inboard engine for spring?

You’ll need to prepare your boat when you take it out for its first excursion during the spring or summer. If you didn’t do this when winterizing your boat, make sure to:

• Change the engine oil
• Replace the oil filters
• Purchase a spare filter to keep with you on the boat

Make sure there isn’t any creamy oil in the lower unit of your engine. Creamy oil means water. Then, hook up your battery and your engine should be good to go.

How do you winterize an inboard motor?

When boat season is over, you’re going to need to winterize your inboard motor. You can do this by checking the antifreeze. You can do this in for steps:

• Gas it up!  

Make sure the tank is full of gas. This decreases the chance that, in the winter, air will get into the tank.

Add a bit of stabilizer in with the fuel. Your owner’s manual should suggest the proper amount. Stabilizer ensures that there isn’t buildup in your fuel tank when it sits for a long period of time. Not just the tank, but also your fuel lines, injectors, and carbonators.

Warm the engine by running it in the water or by running it with an adapter.

• Add some antifreeze.

In addition to adding antifreeze, make sure you also spray some fogging oil into the engine. Antifreeze prevents any water and condensation in your engine from freezing. Fogging oil protects the internal surfaces of your engine from corrosion. It also lubricates the cylinder walls and can prevent it from scuffing the next time you start the engine in the spring or summer.

• Change the oil and the oil filter

Yes, you can leave this for the spring. However, since your engine is already warm, why not drain and change the oil now? If the transmission and engine are contaminated with dirt, you don’t want it doing any harm in the winter.

• Do a final check.  

While you’re at it, feel free to do a routine check for each of these systems and parts:

• Exhaust system: look for corrosion
• Hoses and clamps: look for damage
• Seal off any cracks to avoid build-up
• Remove the battery and keep it on a trickle charger
• Keep bug repellant on board
• Acquire a good winter boat cover
• Stay vigilant and make sure it is insured for theft and damage

The Takeaway:

There are plenty of engine options to choose from: between inboard to outboard to surface drives. Inboard motors are great for waterskiing, wakeboarding, and other leisure and sports activities because of its amazing wake control.

They can also tow well and clear transom for tow ropes.

Take proper care of your engine.

No matter which inboard engine you decide to purchase, make sure you are taking proper care of it. Taking good care of an inboard motor will prevent any bigger issues down the road.

Flush the engine as often as you can. While you’re waiting for the water to run clear through the engine, check any hoses, connectors, pumps, stuffing box, and make sure to look for the smell of fuel in the engine compartment.

You should also winterize your engine properly and make sure the oil and filters are changed before you start it back up in the spring. You can change them in the spring before you start it up for the season, but it will be much easier to do that maintenance when you’re winterizing your boat .

Needing a change?

The idea of changing out an old inboard engine for a new one, know that there are a lot more things to consider than just the price tag of the new engine. There are a few things you should do if you do find that this option is the best for you:

• Make a list of the yards and mechanics around you who have done similar repowering jobs.
• Look at yelp reviews and ask around to see if customers are happy with their service.
• Consider changes you’ll have to make if the horsepower will increase or if the motor itself will be lighter. For example, if you’re swapping from an old diesel engine to a newer, lighter model. If you’ll be making changes like this, contact the boat manufacturer to see if you’ll need to make any structural alterations.
• Consider the changes necessary if you convert from gas to diesel.
• Also, consider the size of the engine. Will there be room for access?
• Will the electrical gauges work with the new engine?

Lastly, don’t let anyone tell you that you can swap an inboard motor with an automotive crate engine because (while they are similar in theory), there are enough differences to cause problems.

Click to share...

Specifications

NOTE: 1 kW = 1.3596 mhp = 1.34102 bhp Fuel condition: density at 15°C = 0.842 g/cm³ Technical data is according to (ISO 8665) / (ISO 3046) Fuel temperature 40°C at the inlet of the fuel injection pump (ISO 8665) Length includes KM35A marine gear (Dimensions may vary with other gears/elbow)

More Information

Winner of the miami 2018 innovation award for the inboard engine category.

The 3-cylinder 3JH40, with an output of 40 mhp, will enable a whole new category of smaller leisure boat owners and commercial vessel operators to benefit for the first time from the efficiency and performance advantages associated with the most recent electronically-managed CR fuel-injection technology.

With an output of 40 MHP @ 3000 rpm (29.4 kW @ 3000 rpm), the 3JH40 is the smallest common rail inboard marine diesel in:

• Displacement, with only 3 cylinders measuring 1.642 L (100 cu in)
• Physical size, measuring 774 x 580 x 632mm
• Weight, measuring 192kg without gear

Through common rail technology, the 3JH40 offers minimal fuel consumption and exceptionally low noise and emission levels, exceeding EPA Tier 3 and EU RCD Tier 2 emission regulations for virtually smoke and odor-free operation.

The 4-stroke, water-cooled 3JH40 is an ideal solution for new builds and repowering applications, specifically monohull sailing yachts and catamarans up to 45ft, small motor boats or sloops, and light duty commercial craft.

*The next largest common rail inboard marine diesel engines are the YANMAR 4JHCR line: 45, 57, 80, 110 MHP.

Drawings Download Drawings

Performance Curves Download Specification Datasheet

Standard Engine Package

• Exhaust mixing elbow [L-type]
• Alternator 12V – 125A
• Flexible mounts
• Mechanical throttle sensor
• Fuel pre-filter with water separator
• Fresh water expansion tank
• Belt safety cover

Optional Accessories

• High-riser mixing elbow [instead of L-elbow]
• Secondary alternator 12V – 125A or 24V – 60A
• Extension harness [3m, 5m, 10m]
• Second station
• TFX Sidemount control head
• VC10 Vessel Control System
• NMEA2000 Engine monitoring system
• Semi 2-pole
• SOLAS including Certificate [factory fit only]
• Hot water kit with cocks
• Extension saildrive leg [75 mm]
• Propeller cone nut kit SD60
• On-board spare parts kit

Operation Manual

Product guide, specification datasheet, technical drawings - bobtail, technical drawings - gear, technical drawings - saildrive, compatible products, gears / drives, controls / panels.

Kanzaki Gears

B25 & C35 Panels

Sign-up to receive the latest information about new products, services, and general updates.

YANMAR’S extensive global service and parts network spans 130 countries and over 2100 locations.

We’re here to help and would love to hear from you. Contact us with inquiries, comments, and feedback.

Elige tu idioma

Choisissez votre langue, velg ditt språk.

Nederlandsk

Portugisisk

Välj ditt språk

Portugisiska

• Request A Test Drive
• Find Your Local Dealer
• Dealer Login

REVOLUTIONARY OWNERSHIP EXPERIENCE

• – Catalyst
• – 4-Star Emissions
• – No Propeller
• – Reduced Insurance Cost

DRIVEABILITY

• • Instant Thrust Response
• • 45° Steering vs Outboard 30
• • First Heater on a Pontoon when Paired with 2.3L
• • Smooth Mechanical Steering
• • More Useable Storage Space than any other Pontoon
• • Walk Thru Access Swim Platform
• • Operate in Shallow, Weedy or Rocky Bottom Water
• • Ability to Extend Boating Season

PEACE OF MIND

• • Closed Cooled
• • AIS Protection
• • Fuel Efficiency
• • Easy Annual Maintenance
• • Trim Not Required for Trailering
• • No Raw Water Pump Impeller to Replace Annually
• • Axial Pump Impeller Design Reduces Clogging
• • 5-Year Factory Warranty

MADE FOR SERIOUS BOATERS

QUIETER OPERATION Indmar’s hull insert design isolates the entire jet pump in rubber, reducing engine noise and pump vibrations (NVH) to deliver a quieter and smoother boating experience.

PRECISE HANDLING A reverse bucket with lateral control has been combined with an exclusive rudder and steering nozzle to deliver class-leading maneuverability at slow speeds and on plane.

SUPERIOR PERFORMANCE Optimized for the enthusiast driver to deliver exceptional agility, superb feedback and multi-sport performance.

STRESS FREE NAVIGATION Shallow draft enables users to safely navigate just about anywhere on the lake. Stress free navigation.

REDUCED TAKT AND ASSEMBLY TIME Indmar’s Plug and Play installation procedure significantly reduces installation time of the pump and engine by up to 50%. Saving boat builders money on installation, while providing the opportunity to increase production.

QUALITY CONSTRUCTION Current jet pump designs require up to 15+ leaks points for installation. Indmar’s EcoJet only requires four, reducing leak points by up to 10+ locations.

MORE COST EFFECTIVE   Lower cost than jet pumps currently available. Less cost in labor to install. Less cost to train installers and less cost for the end user to maintain.

PEACE OF MIND PROTECTION

Not only does Indmar’s Raptor Series offer more power, more torque and better fuel economy. More protection and peace of mind also come standard with our full 5-Year Factory Warranty.

Indmar’s 5-Year Factory Warranty is administered directly through Indmar Products, Inc. and is fully transferable. There are no third parties or insurance involvement. The Raptor Series is an exclusive line-up that defies every challenge, especially the test of time.

5-YEAR WARRANTY

FACTORY BACKED

TRANSFERRABLE

COMES STANDARD

FIND OUT WHAT HAPPENS AFTER THE SALE

THE INDMAR OWNERSHIP EXPERIENCE Buying a boat with an Indmar Marine Engine is like joining a family. A big thrill-seeking, adrenaline-fueled, happy family. Take comfort in knowing that our relationship does not end the day you drive off into the sunset with your new boat. Throughout your entire ownership experience, from the engines quality and performance, to the buying, maintenance and service, we at Indmar and our boat building partners along with our dealer network, are committed to providing you outstanding customer service.

Because it’s an Indmar, there is very little required maintenance and when you need maintenance you have over 1,800 locations to service you no matter where you are in the world. Indmar personally trains and certifies each of their authorized technicians. Whether you are looking to purchase a new boat or service your existing one, you can expect a first-class experience with professional service, high quality genuine Indmar parts and certified technicians that have been specially trained by Indmar to ensure your service or repairs meet our specifications.

RAPTOR MODELS

The Ultimate Guide to Small Boats: What Are Your Options?

Small boats are where many people discover a love for the water, and if you’ve been browsing our Boat Finder Tool looking for small boats that would be ideal for your needs, you’ve surely encountered many options. 

Small boats are less expensive to buy and operate than large ones, are easier to tow or load on a trailer, and can sneak into tiny waterways that bigger boats can’t access.

Small boats also have an esoteric value that’s difficult to pin down. There’s something special about being physically closer to the water, surrounded by nature without all the extra tools and features found on larger, more complex boats. 

In fact, many boat lovers who own large boats also have a small boat or two that they love and enjoy just as much as their bigger craft. But which small boats would be best for you? To make the search easier, we'll review the top 10 small boat contenders.

Types of Small Boats

Inflatable boats, aluminum fishing boats.

• Pontoon Boats

Car-Toppers

Canoes and kayaks, personal watercrafts (pwcs).

Jon Boats are among the simplest and most popular boats around. Many consist of little more than an aluminum hull with a flat bottom and a squared-off bow, bench seats, and an outboard or electric outboard engine. They’re incredibly easy to launch, load, and store and are among the least expensive options for buying a boat .

Skiffs are another form of very simple, basic, all-purpose utility boats. What exactly makes a boat a skiff? This is a catch-all term often used to describe any relatively small and open boat. Due to this, there’s an extensive range of candidates.

Dinghies come in many shapes and sizes and in different versions that can be rowed, motored, or sailed. But they all share a few common traits: they’re usually very small (eight or 10 feet is standard) and are often used as tenders to transport people and gear from a boat to shore.

Inflatable boats come in two basic styles: those that are completely inflatable and those that have a rigid hull surrounded by an inflatable “collar” or ring (usually called a “RIB,” short for rigid inflatable boat). 

Most inflatables are made of materials like Hypalon or PVC fabrics. Their main advantage is the ability to bounce off anything they might hit. Still, RIB versions are also considered seaworthy and used in many commercial and search-and-rescue applications and for recreational purposes.

Aluminum fishing boats come in all shapes and sizes, the only common denominator being that they’re constructed of aluminum. Aluminum boats tend to be light, relatively inexpensive, and fuel-efficient.

Small Pontoon Boats

Although there are some very large and costly pontoon boats on the water, plenty of small models are available that are easy to trailer, easy to afford, and still get you a taste of luxury on the water. There are even different models and designs ranging from mini fishing pontoons to small performance pontoon boats.

Learn more in Buying a Pontoon or a Deck Boat?

This is another catch-all category of boat, with one common denominator: if a couple of people can lift it up and secure it to a roof rack on a car, the boat’s officially a car-topper. Usually, these are very small, simple boats, like Jon boats and dinghies.

These small crafts are popular, and even though most don’t have any mechanical propulsion, they’re still boats. In fact, there are some shockingly advanced models designed for specific purposes (such as fishing or maximum speed). Many boaters develop their initial love for the water while paddling or pedaling on a canoe or kayak.

While there are some large and rather complex jet boats , some small ones can be pretty thrilling to drive. Most have inboard jet engines that create thrust by blasting high-pressure water through a nozzle rather than spinning a propeller. However, there are outboard versions of jet engines, too.

Many people think of personal watercraft (PWCs) more like motorcycles of the water, which has led some to refer to them as waterbikes, or boatercycles. But despite their small size and limited passenger capacity, these are still boats in every sense of the word. They’re also among the most exciting to drive, and many are capable of neck-snapping acceleration, hair-raising high speeds, and exhilarating hairpin turns.

So—have you made up your mind as to which small boat you’d like to own? With all these options, it’s no surprise if you’re still trying to determine which one is right for you. No matter which ones you may be considering, however, one thing is a sure bet: whether it’s the only boat you have or it’s one of several in the family fleet, your love of the water is only going to grow when you spend time on your own small boat.

Read Next: Choosing the Right Boat Type for You

Editor’s Note:  This article was updated in December 2022.

Join Our Newsletter!

Get community news, buying bargains, and how-to guides at your fingertips.

• AROUND THE SAILING WORLD
• BOAT OF THE YEAR
• Email Newsletters
• America’s Cup
• St. Petersburg
• Caribbean Championship
• Boating Safety
• Ultimate Boating Giveaway

Lightweight and Small Outboard Motors for Sailboats

• By Ed Sherman
• Updated: April 22, 2019

When you’re facing strong winds and you need to get somewhere fast, it’s time to break out a small outboard such as an aluminum genny. A dependable outboard that has enough horsepower to get you to the racecourse and back, yet is light enough not to be a drag on your race results, is invaluable. Most racing sailors don’t need as much horsepower as they might think.

An eight-horsepower outboard, for example, will push a 30-foot, 6,000-pound boat along at 6.5 knots. Anything bigger will weigh more than 90 pounds and isn’t suitable for lifting on and off the stern. Here’s our roundup of some of the best outboard motors for sailboats, and some help in deciphering what’s right for your boat.

We focus our attention on engines available under nine different brand names. Two of the best-known names, Johnson and Evinrude, have dropped out of the small-engine end of the market as part of parent company Bombardier Corporation’s restructuring of these two companies. Currently they’re advertising the availability of six- and eight-horsepower four-stroke models in 2003. Another dropout in the mini-engine market is Suzuki. Their smallest two-stroke is a five-horsepower unit and in the four-stroke configuration, a 9.9 horsepower. Brand and corporate shuffling aside, of particular interest is whether the companies that are building nine horsepower- and-below engines have incorporated four-stroke technology into the lower horsepower range, since it’s now beginning to dominate the mid-sized and larger outboard engine market. The answer to that is yes, to a point.

Two or Four Stroke Outboards for Sailboats

Outboards are either two or four-stroke engines, and the four-strokes have definitely gained favor in recent years for several reasons: they’re quiet, they use much less fuel, and they run more cleanly. Since no oil is mixed with the fuel, the classic two-cycle smokescreen isn’t a factor. In a four-stroke, the piston reciprocates inside the cylinder four times for each power stroke (that is, each time fuel combusts). Rather than opening ports cut into the sides of the cylinder, intake and exhaust valves controlled by a camshaft allow a fuel/air mix to enter the combustion chamber with the suction created by the piston as it moves inward in its cylinder. Exhaust gases are forced out of the cylinder as the piston moves outward.

By carefully designing the camshaft, engineers minimize the amount of time that the intake and exhaust valves are both open, considerably reducing the amount of unburned fuel that exits with the exhaust stream. The end result? Fewer emissions and greater economy.

But they do have at least one distinct disadvantage for the racing sailor, and that’s weight. For example, four-stroke engines in the five-horsepower category are about 20 percent heavier than comparable two-stroke engines of the same horsepower. The good news, however, is that only amounts to between 10 and 15 pounds, depending upon the engine. Four-stroke engines cost more, also, but the improved technology may be well worth it.

If you’re totally weight and price conscious, you’ll want a two-stroke engine. But, if you think you can lose the weight elsewhere, a clean, quiet four-stroke without the hassle of mixing fuel could be the answer. In fact, Mercury/ Mariner’s newest six-horse four-stroke engines are actually 18 pounds lighter than their older two-stroke equivalents–a testament to the benefits of improved design and technology.

Environmental regulations are pushing manufacturers towards four-strokes as well. Four-strokes meet emission control standards, and US Environmental Protection Agency regulations mandate that new outboard and personal watercraft engines reduce engine hydrocarbon emissions by 75 percent by 2006. Environmentally conscious sailors should look for either a C.A.R.B. (California Air Resources Board) “very-low” or “ultra-low” designator, or a specification indicating 2006 EPA compliance.

How Much Horsepower Do You Need?

The amount of power you’ll need depends on several key factors. The first consideration is the weight of your boat. The second is the boat’s wetted surface. Full-keel boats not only weigh more but also have more surface area to push through the water. My rule of thumb here is to start with a two-horsepower engine for small centerboard and keelboats less than 1,000 pounds, and add one horsepower for every 1,000 pounds of displacement. For more exact, albeit complex formulae, I suggest The Propeller Handbook by Dave Gerr (McGraw-Hill 2001).

Compare your boat’s dimensions against what existing classes have found to work; for example, a Melges 24 at 1,650 pounds is typically rigged with a three-horsepower short-shaft engine, while a J/80 at 2,900 pounds can still squeak by with a long-shaft, three-horsepower engine. A 1,790 pound J/22, on the other hand, typically uses a four-horsepower long-shaft engine. On the larger end of boats using outboards, you’ll find the outboard version of the J/29, at 6,000 pounds, requires a 7.5-horsepower long-shaft engine.

If you are intending to do some cruising, or even long deliveries to regattas, an option that’s available on some engines is a high-thrust propeller. On larger boats, this option can save weight over a bigger engine and really make a difference when trying to punch through a strong tide or headwind. High-thrust props cost more and are less fuel efficient–but they can save weight and give you more power.

Once you’ve determined how big an engine you’ll need, the next step is to begin comparing features in the given horsepower range you’ve selected. There are nine manufacturers included in our roundup, but some of their brands are identical products with different labeling. In the smaller sizes, the Mercury and Mariner brands are identical. As for the Nissan and Tohatsu engines, Tohatsu builds them all. Yamaha, Suzuki, and Honda all offer competitive products as well, but they’re all independent brands.

What to Look For in Lightweight Outboard Motors

In the small engine sizes, specific features to look for can be reduced to several key items. For some, having an integral fuel tank will be important. The smallest engines have integral tanks that hold only a quart or two of fuel–good enough for an hour or two of operation. No manufacturer lists fuel consumption because the size boat the engine is pushing and the wind and wave conditions vary widely. Compare the size of the tanks, and whether you can attach a remote tank for longer trips. The extra weight and space of a separate fuel tank will be a burden on smaller ultra-light boats.

The availability of long- and short-shaft versions in the horsepower size you need is also important. Honda for example offers 20 and 25-inch transom height (long or short shaft) right down to their smallest BF2 (two-horsepower) model. Mercury and Mariner only offer a 15-inch short-shaft version on their 3.3- and 2.5-horsepower engines. Shaft length is measured from the top of the bracket to the tip of the shaft–make sure your shaft is long enough to position the propeller and cooling water intake deep enough below the waterline to avoid cavitation when the boat pitches through waves.

Other specifications that are worth comparing are whether the engine is equipped with a simple forward and neutral gearshift or if the unit has a full functioning forward-neutral-reverse gear unit. If you’re going to be doing long deliveries to regattas, or in the larger sizes for a racer/cruiser configuration, consider whether or not a charging system is part of the engine package, and if so, it’s output. Will it be adequate to keep your battery recharged and power things like a tiller pilot and running lights? Also, on the larger engines check to see if electric starting is available, or offered as a standard feature. Having it can be the difference between pain and pleasure.

If you are racing in a strict one-design group, check any class rules that apply to outboard engines. Issues related to brackets, storage of the engine and/or alternative weight might be issues, so be sure to check with your class before making any final decision.

Ed Sherman is the author of Outboard Engines, Maintenance, Troubleshooting and Repair, International Marine/McGraw Hill and a contributing editor to Sailing World.

• More: Accessories , clothing , Sailing Gear

Comfort Rules with Mustang’s Minimalist Buoyancy Aid

Smart Polars Are Here

Reproofing May Be Required

Wingfoiling Gear: A Beginner’s Guide

Barcelona Breeze Increase Spikes Intensity

Luna Rossa Dominant on Busy Day in Barcelona

One and Done on Drifter Day of Cup Challenger Series

Shocks and Drops At Louis Vuitton Cup Start

• Digital Edition
• Customer Service
• Privacy Policy
• Terms of Use
• Cruising World
• Sailing World
• Salt Water Sportsman
• Sport Fishing
• Wakeboarding

Beta Marine Diesel Engines

Heat exchanger cooled marine propulsion engines.

Since 1987 Beta Marine has developed an enviable reputation for providing quiet and smooth running marine diesel engines to suit a wide range of applications. Built upon a marinized Kubota engine block, Beta Marine diesel engines are renowned for longevity, reliability and providing the lowest total costs of ownership. Replace your inefficient, high-maintenance diesel engine with a new, reliable, and quiet one and feel the difference in efficiency and performance. Buying from us will lessen maintenance time and money and give you peace of mind.

• 5 Year Self-Service Engine Warranty
• Affordable and Widely Available Parts
• Custom Engine Mounts & Exhaust Risers
• A Complete Engine Package
• ISO 9001 Quality Assured Manufacturing

Beta 14 to 38 Sales Brochure

Beta 43 to 85T Sales Brochure

Small Engines (14 – 38 HP)

Beta 14 9.9 kW / 13.5 hp @ 3,600 rpm

Beta 14 atomic 4 replacement.

Beta 16 12.5 kW / 16 hp @ 3,600 rpm

Beta 16 atomic 4 replacement.

Beta 20 14.9 kW / 20 hp @ 3,600 rpm

Beta 20 atomic 4 replacement.

Beta 25 18.5 kW / 25 hp @ 3,600 rpm

Beta 25 atomic 4 replacement.

Beta 30 21.7 kW / 30 hp @ 3,600 rpm

Beta 35 24.7 kW / 35 hp @ 2,800 rpm

Beta 38 27.0 kW / 38 hp @ 3,600 rpm

Mid/large engines (43 – 83 hp).

Beta 43 32.6 kW / 43 hp @ 2,800 rpm

Beta 50 34.0 kW / 45.6 hp @ 2,800 rpm

Beta 62T 46.2 kW / 62 hp @ 2,800 rpm

Beta 70T 52.0 kW / 70 hp @ 2,800 rpm

Beta 85T 62.0 kW / 85 hp @ 2,800 rpm

Epa replacement program engines.

Beta 10 7.5 kW / 10 hp @ 3,000 rpm

Beta 45T 33.5 kW / 45 hp @ 3,000 rpm

Beta 60 36.5 kW / 56 hp @ 2,700 rpm

Beta 75 56.0 kW / 75 hp @ 2,600 rpm

Beta 90 67.1 kW / 90 hp @ 2,600 rpm

Beta 90T 67.1 kW / 90 hp @ 2,600 rpm

Beta 105T 73.1 kW / 98 hp @ 2,600 rpm

Beta 115T 85.7 kW / 115 hp @ 2,800 rpm

Our Commitment

Whatever it takes. That sums up our commitment to our customers and what we’re willing to do. From new product solutions, worldwide dealer support, sponsorships, and an online retail service, we continue to fine-tune our service approach to supply what you need.

Innovative Engineering

Our reputation as innovators in the marine industry comes from years of research, development, and manufacturing. Our in-house machine shop allows for constant development and our unique relationship with GM puts more muscle behind our innovation.

State of the Art Technology

In an industry that is constantly evolving, staying at the forefront of technology advancement is key.  At Marine Power we are continuously developing our products and solutions to take advantage of the newest technology, from Bluetooth connectivity to the latest ECM controllers.

Worldwide Tools

We hold the tools, talent, and technology to support dealers worldwide. Our force comes from tremendous support throughout the world, with an extended reach to over 8,000 dealers. It’s easy to see why Marine Power can deliver.

Find Your New Engine Today

Whether you are in need of a replacement engine or just looking to add more power to your boat, Marine Power has got you covered with our line of longblock, partial, and complete engine packages.

• Enjoy peace of mind on the water knowing you're covered by our comprehensive engine warranty program
• Optimize performance with increased power and fuel efficiency for any marine application
• Take advantage of worldwide dealer support providing you maximum serviceability

A Perfect Match

From airboats to jetboats and everything in between, Marine Power has the engine to fit your application.

Dealers & Distributors

Support network.

We are focused on building and maintaining a large support network of dealers and distributors worldwide.

ENGINE CONFIGURATIONS

Base engine.

Authentic GM Marine longblock engines manufactured on GM production lines strictly for marine use. Available in both standard and counter rotation, Serves as the base for all Marine Power engines.

The ParPac is a partial engine package. Built using an authentic GM base engine and includes an intake, carburetor, electric fuel pump, and ignition system,

The SportPac is a Complete Inboard engine package. Ideal for a full re-power of the weekend cruiser or family ski boat. Compatible with state of the art  MEFI 6 fuel injection to increase performance and fuel consumption.

The EnPac is a Complete Sterndrive engine package. The perfect drop-in solution for replacing your Mercruiser, OMC, and Volvo sterndrive engines. Compatible with state of the art  MEFI 6 fuel injection to increase performance and fuel consumption.

The AirPac is a supercharged Air Boat engine. Consider this your go-to small block engine. Super doesn’t begin to cover the power this engine is packing. High-flow cylinder head design with Swirl-Wing technology induces combustion chamber swirl.

The JetPac is a Complete Jet Boat engine package. The JetPac comes equipped with fuel injection and makes the perfect repower or upgrade for your jet boat applications.

ENGINE APPLICATIONS

Delivering performance, replacement engines.

From longblock to complete sport performance engines.

DELIVERING POWER

Jet engines & pumps.

Solutions for your most demanding jet boat requirements.

DELIVERING INNOVATION

Airboat engines.

Introducing the LS family of fuel economy airboat engines .

Our Dealers

View our dealer locations around the world and find contact details for your nearest dealer.

Drop us a line

You can contact us by filling in this form any time you need professional support.

Learn more about us and find resources that will help you with all of our products

Inboard vs. Outboard Motors

Table of Contents

Last Updated on June 26, 2024 by Boatsetter Team

Inboard vs outboard motors, which is better? Although a divisive one, this discussion is as important as it is overdue. Boat owners, be they rough and ready fishermen or pleasure sailing dandies, usually fall into two camps: those who sing the praises of inboard motors and those dedicated to all things outboard. 

The first thing to notice is that over the last decade (or two), there has been a growing trend of new boats coming equipped with outboard motors. According to survey data by the NADA , the boating industry sold more outboard motor-powered crafts over the last few years than ever before. In fact, more than 165,500 outboard motors were sold in 2016. Some pundits have argued that this is due to consumer preferences, while others have said it is more cost-effective to install for manufacturers. 

However, does this mean that this variety of motor trumps the inboard? After all, why would outboard motors become the standard for boating power if they were not the best?

Not so fast.

Every experienced owner of a boat has a preference. This is even more true of manufacturers. Ask anyone in the boating game what type of motor they prefer, and you will get a different answer. You are likely to start up a fierce debate – be warned! Whatever you might have heard at the port , it is vital that before you attempt to choose your ideal style of motor, you must set aside any preconceived notions you may have.

The truth is: neither motor wins outright in the perennial inboard vs. outboard debate. Like your own kids or car collection, each one has its own merits and quirks. Nevertheless, the motors do outclass one another in specific categories and areas. As such, must depends on what you plan to do with your boat and your personal preferences. Freshwater or saltwater? Maneuverability or stability? Speed or stamina? All of these questions, alongside a million more, ought to be considered.

Inboard Motors

True to its namesake, an inboard motor is fixed inside the boat, typically at the hull . Petrol and gas versions have combustion engines with firing cylinders, whereas electric models differ. Inboard motors are often housed in a large box in the middle of the vessel. This center of gravity is a huge benefit to a drifting experience.

You can spot an inboard at the port by the distinct rudder used to steer the ship. Fishing trawlers on the high seas rely on these of their lower center of gravity. At the same time, slalom skiers enjoy their smaller wake . Larger vessels, like yachts, also use inboard motors but require bigger models, which cannot be placed on the rear of the hull.

Making a judgment on the merits and drawbacks of the inboard is tricky as those who prefer them have their own set of valid reasons. While they need a large box in the middle of the ship to hold the engine – something that can reduce much-needed deck space – they are quieter than their outboard counterparts. This renders them more suitable to the socialites out there who love entertaining. And let us not forget those fishing folks. A quieter boat is less likely to disturb your prey, ensuring a bigger and better catch is had by all.

Albeit ever so slightly more expensive than their outboard counterparts, inboard motors have a penchant for fuel-efficiency. This is because they are modeled on car engines. Moreover, this means that they boast better torque and horsepower for some hair-raising water antics.

A major – and potentially dangerous – downside to the inboard is that it can be a fire hazard. Unfortunately, countless vessels have been damaged and destroyed by fires that began in the inboard motor. Yet fear not. Running a bilge blower can solve that issue.

Check out this post for more tips on  how to look after your pride and joy .

Outboard Motors

With sales figures as high as those quoted earlier, it is little wonder that the market for outboard motors is huge. No, gigantic. What this means for consumers is that there is ample choice out there. There is an outboard motor to suit any and every function for fishing, recreational boating, or small commercial outfits. 

The engine of an outboard is rear mounted on the boat and is commanded by a handle for steering and titling. The propellers can be lifted out of the water completely, which means that transporting and storing them when not in use is a breeze. More so, this feature means that the propellers avoid sitting in the water for prolonged periods, protecting them from erosion and the growth of organic matter. This maximizes durability, of course.  

Another notable advantage of the outboard is that its position on the boat makes replacing the motor a simpler process than the inboard. Indeed, replacing an inboard is often an expensive and time-consuming task. This capability means that you can easily upgrade to a new, more powerful motor should you wish to – all without the need for specialist tools or professional expertise. This same simplicity also carries over to repairing and maintaining an outboard. That is if you need to do so. Outboard motors are famous for their dependability.

Yet, outboards are not impervious to faults. A significant drawback of this style of motor is that its power can often leave much to be desired. The bottom line is: outboard motors are insufficient for large vessels. Well, unless you want to spend your life savings on fuel. Finally, outboards take up space. And lots of it. If you wish to entertain on your boat, which is your primary purpose, you might want to consider the inboard. Again, much depends on your needs.

But before we move on to cost, maintenance, and power comparisons, let us talk hybrids. Oh yes, that is right, here it is, the curveball: the happy medium, the center-ground. Although the hybrid resembles more the outboard with the motor mounted at the rear of the hull, the propeller shaft passes through the boat’s hull. Sharing most of the pros and cons of the outboard, the hybrid also comes with the challenges of the inboard’s positioning.

Cost Comparisons

Of course, the larger the engine, the more expensive it will be to purchase. But you may want to also consider maintenance and replacement costs, along with the life expectancy of the motor design. 

For instance, inboard motors typically have a longer life expectancy than outboards. Meanwhile, maintenance requirements, based on hours of use, tend to favor the inboards. To be clear, inboards, on average, can run for near two thousand hours before they might require attention, whereas outboards usually run for around 750 hours before a service is needed.

Yet pay attention : purchasing an inboard motor will be heavier on the purse strings and can entail insurance coverage with more expensive premiums.

Sounds confusing, doesn’t it? Never fear. This  boat payment calculator  can assist you with the difficulties of working out finances by working out the running costs of your chosen engine. It is where boating veterans of all stripes get their knowledge.

Maintenance Costs

It can be a boring topic. However, you ignore it at your peril: maintenance. As touched upon earlier, outboard motors are used praised for their low, no-nonsense maintenance requirements. Situated at the rear of the hull, their housing protects the inner workings of the motor from the environment.

Hybrids and inboard alike share the same issue: positioning. At the boat’s bilge, steam, damp, and good old H20 can wreak havoc inside the motor when you need to open it for maintenance, potentially causing you a pain in the behind (and wallet). Compounding matters, accessing them is also tricky. This is primarily caused by the petite hatch in their housing, giving you less wriggle room than an outboard.

When you wish to place your boat on land, outboard motors also do not have a drain due to their placement on the boat. This means that excess water can sit around, again creating trouble if you decide to take your boat out of the water. Conversely, inboard varieties avoid this design, which protects them from possible damages caused by moisture.

Power Comparison

POWER. It is a topic you cannot avoid considering. The directional thrust and integral skeg of the outboard mean that a boat equipped with one of these bad boys is nimble on the water, especially at low power and speed. The benefits of this are countless. However, an outboard motor mostly enables you to navigate shallower waters better and park your boat up neatly.

Although there is one thing to bear in mind: despite having a superior power to weight ratio than inboards, outboards lack the total torque to drive big, beefy vessels. However, enthusiasts generally circumvent this issue by adding a second motor. Nowadays, it is not uncommon to see three or four motors adorning their transoms.

Moving on to the inboard, describing them is easy: they are the complete opposite of the outboard in this regard. The fixed position of the propellers under the middle of the boat reduces maneuverability, particularly at lower speeds. This is not to imply the inboard is a slug, however. They are adored by water sports enthusiasts worldwide as they have better wake control, major towing power, and a clear transom for tow ropes. If you are into wakeboarding and water skiing, then an inboard is for you. Besides, a lower center of gravity also helps cut through heavy ocean waves.

So, Which One is Best?

There you have it: a complete guide to outboard vs. inboard motors.

To recap, the advantages of an inboard motor are that they have brilliant fuel efficiency, superior torque and power, and increased life expectancy, and quiet operation. Whereas its downsides are that there is reduced interior space, higher purchasing costs, labor-intensive maintenance, more complex repairs, and full boat winterization is required.

Outboard motors, on the other hand, have a myriad of sought-after traits. Their full portability, easy maintenance, space-saving storage, and simple winterizing procedures, significantly lower price tag, extra interior space, and higher potential top speed. Still, do not forget the challenges. Some of them might break your choice. Most notable of which include low power and torque, which limits their suitability for vessels of certain sizes.

While there are many pros and cons to inboard and outboard motors, it is important to bear in mind that making the right choice is completely up to you and your needs. You may find a better outboard, despite setting out to buy an inboard and vice-versa. The size of your boat, desired maneuverability, boating frequency, local climate, and favorite water activity are essential factors to consider.

Good luck, and remember to do your research. The right decision will enrich your boating experiences to no end and might even prove gentler on the bank balance.

Boatsetter empowers people to explore with confidence by showing them a world of possibility on the water. Rent  a boat,  list  your boat, or become a  Boatsetter captain  today.

Browse by experience

Explore articles

Fishing Licenses: Explained and Simplified

Boating Lakes in Illinois

Boat Ownership 101: Common Mistakes and How to Avoid Them

Captains for Clean Water: Protecting Aquatic Ecosystems | #MindYourWake Series

• Powerboat Level 1
• Powerboat Level 2
• Powerboat Intermediate
• Powerboat Advanced
• RYA Tender Operator
• RYA diesel engine course
• Outboard engine course
• Repower your boat
• Engine servicing
• On the water service
• DD Marine expertise
• Small engines 10hp to 45hp
• Medium engines 43hp to 99hp
• Large, hybrid and saildrive engines
• Fact sheets
• Inboards and outboards
• Water & heating systems & diagnostics
• Fabrication and components

We can repower your sports boat or yacht to get the most out of it. We specialise in the range of quiet, reliable and economical Beta Marine small engines, from 10hp up to 45hp and designed for smaller boats and yachts. We also provide a range of small engine parts and kits. For full engine guides and spares see the bottom of the page.

2 cylinder, naturally aspirated, diesel propulsion engine developing 10 bhp.

2 cylinder, naturally aspirated, diesel propulsion engine developing 13.5 bhp.

2 cylinder, naturally aspirated, diesel propulsion engine developing 16 bhp.

3 cylinder, naturally aspirated, diesel propulsion engine developing 20 bhp.

3 cylinder, naturally aspirated, diesel propulsion engine developing 25 bhp.

3 cylinder, naturally aspirated, diesel propulsion engine developing 30 bhp.

4 cylinder, naturally aspirated, diesel propulsion engine developing 35 bhp.

4 cylinder, naturally aspirated, diesel propulsion engine developing 38 bhp.

4 cylinder, turbo-charged, diesel propulsion engine developing 45 bhp.

Beta Marine small engine range

Beta Marine 10 to 45hp diesel small engine range

Voyage kit medium engine

Robust plastic toolbox parts kit for Beta 28, Beta 30, Beta 35, Beta 38 and Beta 45 engines.

Voyage kit small engine

Robust plastic toolbox parts kit for Beta 10, Beta 14, Beta 16, Beta 20 and Beta 25 engines.

Beta Marine has provided some helpful guides to assess which is the best engine for your boat, plus installation guide and spares lists.

• To view or download the Beta small engine range brochure – click here
• To view or download the Beta Marine engine installation guide – click here
• To view or download the Beta engine and vessel length guide – click here
• To view or download the Beta B10 to B25 engine spares list – click here
• To view or download the Beta B30 engine spares list – click here
• To view or download the Beta B35 to B38 spares list – click here

If you would like to know more about Beta Marine engines or have a general query please fill in the form below and we will respond.

Send message clear

The top of this web page is an Illustrated Guide with photos of the motors and specifications to the right. At the bottom of the page is a Sortable/Searchable Table that lets you compare motors easily. If you are going to be using the table extensively the page is best viewed on a computer rather than smartphone or tablet.

• Illustrated Guide

The motors are organized in alphabetical order by manufacturer, then by model line. For the specifications we have tried to make it a user friendly as possible. If there are 3 models in the line, we will give the specs for each model with a comma in between. If there are many models, we give a range from without lining the specs up with specific models.

• Sortable/Searchable Table

The table can be searched with any keyword – manufacturer, for instance, or can be sorted by any of the columns: Peak kiloWatt power, Continuous kiloWatt power, estimated HP equvalent, Voltage, Dimensions (Length, Width, Height), Weight, RPMs, Type of motor and cooling system (air, liquid, water), and whether it is regenerative – capable of recharging when the boat is under sail propulsion.

All specifications are taken from the manufacturers’ websites or brochures without any independent verification. There is a lot of variety in the way manufacturers detail the attributes of their products, particularly when it comes to ‘Power’. Some use peak power as the measurement, some use continuous power, and there are other variations. Some quote minimum RPMs for their motors, others quote maximum RPMs. There is also no set standard for ‘horsepower equivalent’. We have tried to present the information as close as possible to an ‘apples to apples’ comparison.

The photographs and drawings are from the manufacturers’ websites and are not shown in any consistent scale.

Power Ratings – measured in kiloWatts kW  power rating quoted is taken from the manufacturer website. Some quote only peak power or continuous power, some quote input power and output power. We have indicated what the measurement is, although in the table we have used peak power as equal to input power and continuous as equal to output. power. HP is ‘HorsePower equivalent’ so that you can get an idea of the power of the motor in comparison to a HP rating you might be more familiar with. As noted above, there is a lot of leeway in how this is interpreted. When manufacturers have provided an HP equivalent we have used that.

• IN THE TABLE , when no HP equivalent has been provided, we have used the continuous power and multiplied it by 1.3 to indicate HP equivalent. We have noted it with an asterisk * when we have done this.

Voltage  is most often referred to on the sites as simply ‘Voltage’. Some indicate nominal or peak, we have used nominal and indicated if peak is also referenced.

Current  is noted when the manufacturer supplies the information. It is not included in the table.

Torque is shown in Newton metres, Nm. A Nm is about 3/4 of a foot-pound, or conversely, a foot-pound is about 1 and 1/3 Nm.

Dimensions of the motors and shaft are shown in millimetres – mm. There are about 300 mm in 1 foot, or about 25 mm in 1 inch.

Weight is in kilograms. A kilogram is 2.2 pounds.

Motor Types 
There are advantages and disadvantages to each kind of electric motor. Some manufacturers use abbreviations to describe their motors, others use the full words. We have used whatever the manufacturer prefers, but when abbreviations are used, this is what they mean:

BLDC: BrushLess Direct Current

PMAC: Permanent Magnet Alternating Current

Information on this page updated August 12, 2024

You may also want to check our Directory of Electric Boat Motor manufacturers, dealers and distributors around the world, or the Plugboats Marketplace of electric boat motors for sale.

Manufacturers in this Buying Guide: Bellmarine • Combi • Damoto • Elco • Electric Yacht • Electrine • EPTechnologies • ePropulsion • E-TECH • Fischer Panda • GreenStar Marine • Huracan • Krautler • Lynch • Mitek • Molabo • NT Systems • Oceanvolt • Piktronik • Synapseo • TEMA • Thoosa • Torqeedo • waterworld

Click on the Manufacturer’s name or red cross on right hand side to open and close window with information and links for that company’s electric electric inboards

Click »» here to see Bellmarine motors for sale from vendors in the Plugboats Market

»» Bellmarine website (EU)          »»  Bellmarine website (USA) »» Bellmarine catalogue (EU)      »»  Bellmarine catalogue (USA)

Bellmarine is a very well established electric boat motor company with a history going back to 1999. They have now been purchased by and are merged with Transfluid, a large scale industrial motor manufacturer. Bellmarine offers a wide range of electric inboard motor configurations, both direct drive shaft and reduction geared. They range from 2 kW to 130kW and come in four model lines: the straight drive Drivemaster, dual motor ModularMaster, geared Thrustmaster and high power Shaftmaster. They are sold as complete systems with optional extras available.

Bellmarine DriveMaster Air Cooled Series 9 Models: DriveMaster 2A, 5A, 7A, 8A, 10A, 15A, 25A, 35A, 50A

• kW : Peak: From 2kW – 50kW | Continuous: From 1.5kW – 40kW • Voltage : 48V – Models 2A, 5A, 7A, 10A | 96V – Models 8A, 15A | 144V – Models 25A, 35A, 50A
• Motor Type : Permanent Magnet AC (PMAC)
• Cooling : Air cooled
• RPM :  1500
• Includes : Motor with mounting brackets and silent blocks • Motor with integrated thrust bearing • Vector control inverter IP65 • NMEA2000 compatible (Apply Transfluid) • Main switch and main fuse • DC-DC converter 12 Vdc • 5m cable for display, lever, key • Quick install / easy connect / plug and play
• Available : Regeneration (with upgrade to battery monitor), Control throttle, display, cooling kit, coupling, shaft with propeller
• Country of Manufacture : Netherlands/Italy
• Price : NA on website

Bellmarine DriveMaster Liquid Cooled Series 9 Models: DriveMaster 3W, 7W, 10W, 15W, 20W, 20W-EVO, 30W, 45W, 55W

• kW : Peak: From 3kW – 55kW | Continuous: From 2.5kW – 45kW • Voltage : 48V – Models 3W, 7W, 10W, 15W, 20W-EVO | 96V – Model 20W | 144V – Models 30W, 45W, 55W
• Cooling : Liquid cooled
• Includes : Motor with mounting brackets and silent blocks • Motor with integrated thrust bearing • Vector control inverter IP65 • NMEA2000 compatible (Apply Transfluid) • Main switch and main fuse • DC-DC converter 12 Vdc 5m cable for display, lever, key • Quick install / easy connect / plug and play • Inlet and outlet liquid connections
• Available : Control throttle, display, cooling kit, coupling, shaft with propeller

Bellmarine ModularMaster Series 3 Models: ModularMaster 40W-EVO, 40W, 60W

• kW : Peak: 40, 40, 60 | Continuous: 30, 30, 50 • Voltage : 48V – 40W-EVO | 96V – 40W | 144V – 60W
• Includes :  True redundancy in case of one motor failure • Aluminum made split power drive • Mounting brackets and silent blocks • Live PTO available • Vector control inverter IP65 • NMEA2000 compatible (Apply Transfluid) • Main switch and main fuse • DC-DC converter 12 Vdc • 5m cable for display, lever, key • Quick install / easy connect / plug and play • Inlet and outlet liquid connections• Closed loop liquid cooling size XL mounted aboard
• Available : control throttle, display, cooling kit, coupling, shaft with propeller
• Country of Manufacture : Netherlands / Italy

Bellmarine TorqueMaster Series 2 Air cooled Models: TorqueMaster 20A, 25A 7 Liquid cooled Models: TorqueMaster 20W-EVO, 25W, 35W, 45W, 65W, 100W, 130W

• kW : Peak: 20 – 130 | Continuous: 15 – 100 • Voltage : 48V – 20W-EVO | 96V – 20A, 25W | 144V – 25A, 35W | 288V – 65W, 100W | 384V – 130W
• Cooling : See above
• RPM :  20W-EVO – 1500, all other Models 3000
• Includes : Motor with mounting brackets and silent blocks • Drop Box with integrated thrust bearing – 225 mm offset • Vector control inverter IP65 • NMEA2000 compatible (Apply Transfluid) • Main switch and main fuse • DC-DC converter 12 Vdc • 5m cable for display, lever, key • Quick install / easy connect / plug and play • Dropbox aluminum made – no cooling needed – low noise and low vibration • Oil temperature sensor • Elastic coupling between motor and Dropbox • DIN120 output (SAE 1410 upon request) – “U” drive possible

Bellmarine ShaftMaster Series 6 Models: ShaftMaster 25W, 35W, 45W, 64W, 100W, 130W

• kW : Peak: 25kW – 130kW | Continuous: 20 – 100 • Voltage : 96V – 25W | 144V – 35W | 288V – 45W, 65W, 100W | 384V – 130W
• Motor Type : Motor Type : Permanent Magnet AC (PMAC)
• RPM :  3000
• Includes : Motor with mounting brackets and silent blocks • Live Pto available • Marine gear with integrated thrust bearing (up to 130 kW) • Oil temperature sensor • Output offset 103 mm • Elastic coupling between motor and transmission • Vector control inverter IP65 • NMEA2000 compatible (Apply Transfluid) • Main switch and main fuse • DC-DC converter 12 Vdc • 5m cable for display, lever, key • Quick install / easy connect / plug and play • Inlet and outlet liquid connections • Throttle lever (TFC) • Self priming pump (mechanical) mounted aboard • Oil-water cooler mounted aboard • Closed loop liquid cooling size XL mounted aboard

»» Combi website

Combi Outboards was founded in 1979 in Giethoorn (‘the Dutch Venice’) to supply rental boats with clean electric power. It is now a leading international supplier of electric propulsion solutions for the maritime market. Combi inboards have all of the operating components in one housing, ready to plug in to batteries, throttle and monitoring systems. Motors are available both AC asynchronous (induction) and BLDC Permanent Magnet. The two larger inboards are dual motor, and can be operated on the Master / Slave principle but can also sail on a single motor. 

Combi Inboard 5 Models: CI-3.5, CI-5, CI-7.5, CI-10, CI-16, CI-20

• kW : From 3.5kW to 20kW • Voltage : 48V • Current : From Nominal –73 / Cruising speed – 50 to Nominal – 417 / Cruising – 240 • HP : From 9HP to 33HP
• Motor Type : Brushless AC asynchronous • OR • Brushless DC Permanent Magnet (PMDC) Cooling : CI-3.5 Air cooled, all others liquid cooled
• RPM :  From 1200 to 1500
• Shaft (cm) : Can be connected to all common propeller shaft sizes
• Includes : Our systems are constructed in such a way that all components are used in a motor housing. You just need to connect only the power cables. The engine foundation is prepared so that it is easy to install.
• Country of Manufacture : Netherlands

»» Damoto website

Damoto is a Dutch developer, manufacturer and distributor of an extensive range of premium electric inboard motors from 2kW to 40kW nominal. The first model dates from 2005 with more than 3000 boats equipped with it, including recreational sloops, charter and rental boats. The motors are now released under the name Damoto eFLOW but have been well known in the international maritime industry for many years.

Damoto eFLOW Original Series 5 models: eFLOW 2.0 Air, eFLOW 2.5 Air, eFLOW 3.0 Air, eFLOW 6.0 Air, eFLOW 11.0 Air

• kW : Nominal: 2kW to 11kW | Peak: 3kW to 15kW max
• Motor Type: Brushless 3 Phase Asynchronous • Cooling: Air cooled
• IP : IP66
• Includes : stainless steel motor frame with silent blocks, motor, thrust bearing, controller in stainless steel casing incl. marine software & PC/handheld connector for motor tuning, main power contactor & fuse, controller cable with connectors (Plug-n-Play)
• Available : Displays, throttle levers, shaft couplings
• Country of Manufacture : Netherlands / Europe
• Price : Not available on website

Damoto eFLOW Liquid Original Series 8 models: eFLOW 3.0 Liquid, eFLOW 5.0 Liquid, eFLOW 10.0 Liquid, eFLOW 15.0 Liquid, eFLOW 20.0 Liquid, eFLOW 30.0 Liquid, eFLOW 40.0 Liquid Dual Motor, eFLOW 14.0 Liquid 4Hybrid Dual Shaft

• kW : Nominal 3kW to 40kW | Peak: 6kW to 80kW
• Motor Type: Brushless 3 Phase Asynchronous • Cooling: Liquid cooled
• Includes : stainless steel motor frame with silent blocks, motor with liquid inlet & outlet, thrust bearing, controller in stainless steel casing incl. marine software & PC/handheld connector for motor tuning, on-board power converter (12V) integrated in controller casing, main power contactor & fuse, controller cable with connectors (Plug-n-Play)
• Available : Displays, throttle levers, cooling kits, shaft couplings

Damoto eFLOW Air All-in-One Series 3 models: eFLOW 2.0 Air AiO, eFLOW 3.0 Air AiO, eFLOW 6.0 Air AiO

• kW : Nominal 2kW to 6kW | Peak: 6kW to 80kW
• Includes : stainless steel housing, motor with silent suspension, thrust bearing, controller module incl. marine software & PC/handheld connector for motor tuning, main power contactor & fuse, connectors on box front (Plug-n-Play), wired & tested
• Available : throttle levers, shaft couplings

»» Elco website

Elco (Elco Motor Yachts) is the oldest electric boat motor company in the world, having been started in 1893 as the the Electric Launch Company to supply electric boats for the Chicago World’s Fair. It offers a full range of outboards, inboards and hybrids. Their Plug n Play system has all wiring and active power components in a marine grade aluminum casting rated IP-65. Can be purchased from the Elco website along with batteries, options and accessories, leading to a one-price checkout. They also have a ‘ Find My Motor ‘ calculator on the site.

Elco Inboards 6 Models: EP-6, EP-12, EP-20, EP-40, EP-70, EP-100

• kW : Peak: From 4.4kW – 73.5kW | Continuous: From 2.5kW – 42.5k • Voltage : From 36Vdc to 144 Vdc • Amps : 70A – 295A • HP : 6HP – 100 HP
• Dimension s: From L: 17” / W: 16.22” / H: 15.8” to L: 35”  /  W: 18.82”  /  H: 19.25” 
• Includes : Motor and controller.
• Available : Motor mounts, shaft couplers, batteries, battery monitor, chargers, cables, and other accessories
• Country of Manufacture : USA
• Price (does not include options) : $US 7,000 – 21,000

Electric Yacht

Electric Yacht is one of the premier US suppliers of electric motors for sailboats with a  Plug-n-Play system designed for DIY installation by “ a competent boat owner using simple tools and the easy to mount Electric Yacht system “. Their systems offer regenerative power while under the sail. 10 years of proven production with over 450 installs. 3 Year Warranty.

Electric Yacht QuietTorque single motor inboards 3 Models: QT5, QT10, QT10 Sport

• kW : Input – 2.5kW – 30kW, Continuous 2kW – 8kW • Voltage : 24, 36 or 48V for Quiet Torque 5.0, all others 48V • Current : 100A – 200A • HP : 10-25
• Motor Type : PMAC (Permanent Magnet Brushless AC) • Cooling : Air cooled • IP :
• RPM : 
• Dimensions : L: 432mm, W: 245mm, H (with mountings): 342mm Adjustable mountings • Weight : 40 lbs, 70 lbs
• Includes : The motors are sold as systems with everything included except the battery, which can also be purchased from the company. The systems can be purchased directly from the website.
• Price : $US 5,000 – 9,000

Electric Yacht QuietTorque dual motor inboards 6 Models: QT20, QT30-Air-Cooled, QT30-Liquid-Cooled, QT40, QT45, QT60.0

• kW : Input – From 20kW – 60kW Continuous – From 16kW – 52kW • Voltage : 48V – QT20, QT30-Liquid-Cooled 72V – QT30-Air-Cooled, QT40 96V – QT45, QT60 • Current : NA • HP : From 25 – 80
• Motor Type : PMAC (Permanent Magnet Brushless AC) • Cooling : Air cooled – QT20, QT30-Air-Cooled, Liquid cooled – QT30-Liquid-Cooled, QT40, QT45, QT60 • IP : NA
• RPM : NA
• Torque : NA
• Dimensions : L: 673mm, W: 534mm, H (with mountings): 534mm Adjustable mountings • Weight : From 135 lbs to 200 lbs
• Price : $US 14,500 – 18,000

»» ELECTRINE website

ELECTRINE is a Korean manufacturer which has focused on maritime electrification since 2010, when the idea of electric mobility was still relatively uncommon. The company was known as LGM until 2020 and has had a consistent R&D effort for many years. They manufacture electric outboards, inboards and saildrives as well as accessories and Lithium-ion batteries using a Carbon Nano Tube heat exchanger technology. There are 7 models in the eINBOARD Line, the ZI40, ZI60, ZI90, ZI115, ZI180, ZI270 and ZI350

E-ELECTRINE e-INBOARD line 7 Models: ZI40 (shown), ZI60, ZI90, ZI115, ZI180, ZI270, ZI350

• kW : (Max): 43, 60, 110, 150, 173, 200, 250 • Operating Voltage (Vdc): 72~96, 288~384, 288~384, 288~384, 288~384, 500~738, 500~738, 500~738
• Motor Type : N/A
• RPM (Max):  8006, 7160, 10,250, 8000, 6204, 3500, 3375
• Torqu e (Max) Nm: 72, 167, 255, 251, 555, 2100, 2700
• Weight | Dimensions (kg | mm) N/A | 390 x 360 x 323, N/A | 390 x 360 x 323, 93.5 | 665 x 468 x 476, 93.5 | 665 x 468 x 475, N/A | N/A, 500 | 902 x 1200 x 733, 500 | 902 x 1200 x 733
• Country of Manufacture : Korea

EPTechnologies

»» EPTechnologies website

EPTechnologies is a complete marine propulsion provider for electric and hybrid vessels. The company specializes in custom electric and hybrid systems, but also has ‘off the shelf’ motors, including the drop-in Stern Drive unit below. The company delivers complete systems including batteries designed and built by EPTechnologies.

EPTechnologies Drop In Unit

• Voltage: 400
• Other: This motor system has been designed by EPTechnologies as a complete drop-in unit for a Mercury Sterndrive. Includes all batteries, controllers and accessories
• Country of Manufacture : Denmark
• Price : Contact EPTechnologies

EPTechnologies Electric Motor

• For boat sizes 60′-250′
• kW (Continuous) : 400 (Peak) : 700
• Torqu e (Max) Nm: 7800
• Other : Can be stacked together for 800kW or 1400kW peak

ePropulsion

Click here to view motors from ePropulsion dealers in the Plugboats Marketplace

»» ePropulsion website

ePropulsion was established in 2012 and is led by a team of technology entrepreneurs that are focused on developing uncompromising, superior products. It was the first company to launch a brushless, direct-drive electric outboard motor in the market. ePropulsion offers a portfolio of electric outboard motors – some of which offer hydrogeneration – pod drives, and inboard motors. The company is focused on products and services for all kinds of electric boats from dinghies and fishing boat to sailing boats to commercial and leisure motor vessels up to 100-feet and displacement of 200 tons.

ePropulsion I-Series T hree (3) models: I-10, I-20, I-40

• kW : 60kW to 140kW • Voltage : H-100: 540 VDC
• Motor Type : permanent magnet motor technology • Cooling : I-10 Air cooled | I-20 & I-40 Water cooled (air cooling optional) • IP : IP67
• RPM :  1500 all models
• Torque : 56 Nm | 111 Nm | 222 Nm
• Dimensions : I-10: 565 x 295 x 380 mm | I-20: 580 x 330 x 380mm | I-40 860 x 485 x 420mm • Weight : 43kg | 45kg | 75kg
• Includes : Weather & impact resistant metal housing contains integrated motor, gearbox, electronic control system, ECU, thermal management system and suspension, Smart 5” Display, ePropulsion Smart System Architecture (eSSA), Advanced driver assistance system (ADAS), Wired & tested, plug & play installation to new boat or retro-fit to existing shaft, NMEA 2000 compatible, CAN Bus communication, Fault diagnosis system & full redundancy design
• Available : Smart throttle, G102-100 battery, propeller, air-cooling, HVAC System, shaft and coupling, charger, remote data access & fleet management with IoT connectivity service
• Country of Manufacture : China
• Price : On application

ePropulsion H-Series Four (4) models available: H-60, H-85, H-100, H-140

• kW : 10kW | 20kW | 40kw • Voltage : 86~115 VDC all models
• Motor Type : permanent magnet motor technology • Cooling : Water cooled • IP : IP67 
• RPM :  H-100: 1150
• Torque : 797 Nm
• Dimensions : H-100: H 433mm  x W 433mm x D 315mm • Weight : H-100: 190kg
• Includes : Weather & anti-corrosion metal housing contains integrated motor and  gearbox, high torque density (max 2000Nm), modular design to extend range and power with extra motors, batteries and controllers, high accuracy position feedback, Boating IoT system enables remote monitoring and integrated management, Customised data for speed, power, track, mileage, safety alarm etc., NMEA 2000 compatible
• Available : Controller, remote control and display – single & dual controls, custom batteries 

»»  E-TECH website

E-TECH is a subsidiary of boatbuilder Starboats that was started in 2008 because they were dissatisfied with other electric motor offerings in the market at the time. The company has developed fixed pods, steerable pods and outboard motors that all utilize an in-water BLDC (BrushLess DC permanent magnet) pod motor in a watertight aluminum casing. The inboard motors are designed to fit any engine bed and any propeller shaft. For in-line hybrid applications, there are shaft endings on both ends of the engine to make an easy and quick in-line installation.

Click here to view motors from E-TECH dealers in the Plugboats Marketplace

E-Tech Standard Inboards 6 Models: 4WG, 7WG, 13WG, 18WG, 23WG, 35WG

• kW : From 4.3kW, 7.1, 11.9, 16.7, 21.5, 33.7 (power measured on the shaft) • Voltage : 48V, 48V, 48V (4WG, 7WG, 13WG) | 72V – 18WG | 96V – 23 WG, 144V – 35WG • HP : 6, 9.5, 16, 23, 30, 45
• Motor Type : Brushless permanent magnet BLDC • Cooling : Water cooled •  IP : 67
• RPM :  (min) From 1100, 1200, 760, 1140, 1520, 2500
• Shaft : 25mm (4WG, 7WG) or f 30mm (10WG, 15WG, 20WG), 8mm spline
• Includes : Controller, battery monitor / display, cabling, joystick (side or top mounting), integrated cooling circuit for controller with Quick-Click connections, main switch, main fuse.
• Country of Manufacture : Poland

E-Tech High Torque Inboards 4 Models: 13 Pod, 18 Pod, 23 Pod, 35 Pod

• kW : From 11.9 kW, 16.7 kW, 21.5 kW, 33.7 kW (power measured on the shaft) • Voltage : 48V, 72V, 96V, 144V • HP : ≈ 16, 23, 30, 45
• RPM :  (min) From 760, 1140, 1520, 2500
• Shaft : f 30mm, 1:10 conic

Fischer-Panda

»» Fischer-Panda website

Fischer Panda is one of the world’s best known manufacturers of marine generators but are also manufacturers of high quality electric boat motors, sometimes marketed under the ‘Whisperprop’ name. They have an “EasyBox” system that is intended to take the guesswork and complication out of purchasing electric boat motors. There are various sample configurations on their website displaying how the EasyBox system is laid out in different boats.

Fischer Panda Easybox DE-Shaft systems 5 Motors: A06-140-6-SH, A50-160-6-SH, B00-150-8-SH 10 kW, B00-150-8-SH 20 kW, B00-300-8-SH 20 kW

• kW : (continuous) 3.5kW – 20kW • Voltage : 48V • Current : • HP :
• Motor Type : PMAC • Cooling : Water
• RPM : 600 – 2500
• Torque : 28Nm – 320Nm
• Dimensions : L: 400mm – 560mm W: 270mm H: 270mm • Weight : 15kg – 96kg
• Includes : EasyBox control, GD2 control panel, throttle
• Available : Battery bank, charger, shore power connection, 230V adaptor
• Country of Manufacture : Germany

GSM Electric (formerly Greenstar Marine)

»» GSM Electric website

GreenStar Marine was founded by a group of Swedish engineers in the 1990s to develop a series of electric propulsion systems, including a patented regenerative technology. All of the company’s systems are direct drive one-gear and complete except for batteries. The website has an interactive tool that shows approximate run times for different sized boats and battery/motor configurations.

GreenStar E-Line 2 Models: E-10, E-20

• kW : Peak – 3.5kW, 5.5kW | Nominal – 2.1kW, 4.2kW • Voltage : 24V, 24V • HP : 10, 20
• Motor Type : Brushed DC • Cooling : Air cooled
• RPM :  1000, 1000
• Torque : Nominal: 20 Nm, 40Nm | Peak: 40Nm, 50Nm
• Includes : Motor mountings, control system, basic system monitor, battery charger, monitoring, speed control, shore power system, cables, propeller shaft with low friction bearings, fixed propeller
• Available : Hydrogeneration, folding propeller, extra DC/DC
• Country of Manufacture : Sweden

GreenStar P-Line 3 Models: P-10, P-20, P-35

• kW : Peak – 10kW, 10kW, 30kW | Nominal – 2.5kW, 5.5kW, 11kW • Voltage : 48V, 48V, 48V • HP : 10HP, 20HP, 35HP
• Motor Type : Brushless AC • Cooling : P-10 – Air cooled | P-20, P-35 – Water cooled • IP : 65 or higher classed components
• RPM :  1250, 1250, 1250 •
• Torque : Nominal: 20 Nm, 45Nm, 85Nm | Peak: 75Nm, 85Nm, 130 Nm
• Includes : Hydrogeneration, motor mountings, advanced control system, system monitor, battery charger, monitoring, speed control, shore power system, cables, propeller shaft with low friction bearings, fixed propeller
• Available : Folding propeller, extra DC/DC

»» Huracan website

Huracan was founded at the beginning of 2012 in Venice with the goal of building entirely electric marine motors with the highest reliability of any on the market. The Thor motor is sold in a housing that includes the controller, with throttle, displays, monitors and other accessories sold separately.

Huracan Thor NOTE : The information for Huracan is presented in a different format from other manufacturers because the Thor is the only model, which provides different power ratings at different motor speeds.

• kW : 10kW at 3000 rpm | 20kW at 4000 rpm  | 30kW at 5000 rpm | 40kW at 5500 rpm • Voltage : 220V • Current : NA • HP : NA
• Motor Type : NA • Cooling : Water cooled • IP : 69
• RPM :  3000 – 5500
• Torque : (at axles): 30Nm at 3000 rpm | 49Nm at 4000 rpm  | 56Nm at 5000 rpm | 70Nm at 5500
• Dimensions : L: 543 mm  H: 300mm W: 191mm • Weight : 40 kg
• Available :
• Country of Manufacture : Italy

»» Kräutler website

Kräutler is a long-established Austrian manufacturer of industrial electric motors. They began construction of electric boat motors in the 80’s mainly because they could not find a product that would live up to the standards of founder Oswald Kräutler. They make motors for industrial and ship use as well as recreational boats and offer a wide range of inboards for any size boat or usage. Krautler has 3 lines of electric inboard motors. The WAd and WAz lines are direct drive and run from powers of 2.0kW to 25kW (WAd) and 6kW to 37kW (WAz). The WA line is made up of motors from 30kW to 100kW, for high speed / planing boats.

Krautler WAd and WAz line WAd – 11 Models WAd 2.0AC, WAd 3.0AC, WAd 4.3AC, WAd 5.0AC, WAd 6.0AC, WAd 8AC, WAd 11.0AC, WAd 15.0AC (48V, Air), WAd 15.0AC (96V, Water), WAd 18.5AC, WAd 20.0AC WAz – 10 models WAz 6,0AC, WAz 8,0AC, WAz 11,0AC, WAz 15,0AC (Air), WAz 15,0AC (Water), Waz 18,5AC, WAz 20,0AC, WAz 25,0AC, WAz 30,0AC, WAz 37,0AC

• kW : (Output) From 2.5kW – 37kW • Voltage : 24V – 144V • Current : 104A – 292A • HP : 3.5 – 50 HP
• Motor Type : • Cooling : Air – 6,0 models to 15,0 models (WAd and Waz), Water for 18,5 models to 37,0 WAz model
• RPM :  NA
• Dimensions : • Weight :
• Includes : Controller, throttle, monitor, display, cables
• Country of Manufacture : Austria

Krautler WA High Speed line 6 Models: WA 100/30, WA 150/40, WA 350/50, WA 350/60, WA 500/80, WA 500/100

• kW : (Output) From 30kW – 100kW • Voltage : 100V – 500V • Current : NA • HP : 45 – 130 HP
• Motor Type : • Cooling : Water
• Includes : Battery, controller, throttle, monitor, display, cables

»» Lynch website

The Lynch motor was invented by Cedric Lynch in 1979 – a unique axial gap permanent magnet brushed DC motor with high efficiency. The company offers three lines – the direct drive Yellowtail, geared drive Marlin and dual motor Swordfish. Motor systems include motor in mounting frame, controller, electronics, throttle and basic battery monitor and control cables. (options available on throttles and monitors) Lynch has 3 lines of electric inboard motors: the Yellowtail, Marlin and Swordfish, although the Yellowtail ‘line’ is only one motor.

Lynch Yellowtail

• kW : Peak – 6.0kW, Continuous – 2.5kW • Voltage : 24 • Current : 120/Peak 250A • HP : 5 – 10
• Motor Type : • Axial Flux ‘Pancake’ Permanent Magnet DC • Cooling : NA • IP : NA
• RPM : 1080 • Efficiency : 88%
• Torque : 16/Peak 35Nm
• Dimensions : NA • Weight : Motor: 14 kg Control  box: 12 kg
• Includes : motor in mounting frame, controller, electronics, throttle and basic battery monitor and control cables.
• Available : options on throttles and monitors
• Country of Manufacture : UK

Lynch Marlin : Marlin 5 Single, Marlin 8 Single, Marlin 13 Single

• kW : Peak – 14kW, 14kW, 26kW • Voltage : 48V, 48V, 72VDC • Current : 140/Peak 350A, 180/Peak 350A, 200/Peak 400A • HP : 10-20, 17-25, 35-50
• RPM : 2160, 2160, 3240 • Efficiency : 90%
• Torque : 18/Peak 38Nm , 36/Peak 44Nm, 36/Peak 72/Nm
• Dimensions : NA • Weight : Motor: 21 kg • Controller: 12 kg (14kg on model 13 Single)

Lynch Swordfish : Swordfish 16V Twin, Swordfish 26V Twin

• kW : 16kW/Peak 30, 26kW/Peak 53 • Voltage : 48VDC, 72 VDC• Current : 180A/350 Peak, 200A/400 Peak • HP : 48-60, 60-75
• RPM : 2160, 3240 • Efficiency : 90%
• Torque : 72Nm/144 Peak,
• Dimensions : NA • Weight : Motor: 27 kg Controllers: 14.5 kg X 2 (29kg)
• Includes : motors in mounting frame, controller, electronics, throttle and basic battery monitor and control cables.

»» Mitek website

Mitek Srl manufactures permanent magnet synchronous electric motors that can be used both as propulsion engines and generators according to the highest quality standards for industrial and marine markets.With more than 10 years of experience, it is a flexible partner that provides competitive products and services for sustainable mobility. Its activities focus on the design, engineering and production of innovative high torque electric motors, which are lighter, smaller and more efficient.

Mitek Inboards : 6 Models: 200015, 200020, 260038, 260054, 260061, 260115

• kW (Continuous / Peak) : 10 / 15 to 85kW/Peak 115 • Voltage : 48V, 96V, 192V, 384V• Current : From 200A/310 max to 320A/600max • HP Continuous / Peak : From 14 / 20 to 114-154
• Motor Type : NA
• RPM : From 1700 to 2200
• Torque : From 88Nm/Peak 205 to 380Nm/Peak 540
• Dimensions : L: 388mm – 588mm W: 370mm H: 370mm • Weight : 32 – 69 kg
• Includes : Standalone

Click »» here to see Molabo motors for sale in the Plugboats Market

»» Molabo website

Molabo was founded in 2016 with the goal of providing safe-to-touch low-voltage e-solutions to enable sustainable mobility worldwide. To achieve this they developed the ISCAD (Intelligent Stator Cage Drive) motor technology and have been granted 10 patents worldwide with automotive and marine OEM (Original Equipment Manufacturer) partners in Europe and China.

Molabo ISCAD V50

• kW : Peak: 80 | Continuous: 50 •  Voltage : 48V
• Motor Type : PM-SynRM (Permanent Magnet Synchronous Reluctance Motor) ISCAD (Intelligent Stator Cage Drive)
• Cooling : Water: 7 l/min, max. 45°C (dual circuit cooling possible)  •  IP67
• RPM : 4350 • Efficiency : 95.6 % (Motor: 97 %, Controller: 98 %)
• Dimensions : L: 265mm, Diameter: 254mm • Weight : NA
• Includes : Available as components or compete set-up including motor, reduction gear, rubber mounts & brackets, 5″ touch display, throttle top or side mount, molaCONNECT & molaLINK (IOT), communication cable set
• Available : Battery and charger packages: LFP 36kWh, 48kWh and 12kWh additions
• Price : Motor: €19,990 ($US 21,000)  •  With all components package (excluding battery): €28,400 ($US 29,900)

Click »» here to see NT Systems motors for sale in the Plugboats Marketplace

»» NT Systems website

NT Systems was established in 2018 by a team that includes experts in boating propulsion systems, electric engineering, electric systems development, and development of hybrid propulsion for the biggest 10-20 meter hybrid fleet in the world. They have a range of compact turnkey electric propulsion systems for commercial and leisure applications with high power-to-weight ratio continuous power from 40 kW up to 450 kW. Their system includes top or side mount throttle levers and all-in-one MFD with integrated propulsion interface, navigation, entertainment, and connectivity.

NT Systems electric propulsion inboards 7 models: C40, C80, C120, C160, C200, C320, C450 NOTE : Direct Drive or Gearbox Version s Systems feature a built-in thrust bearing, allowing for direct shaft mounting and use of the propulsion system in a direct drive configuration for simplified installation. Systems are also compatible with various marine gearboxes, allowing you to adjust the output RPM and torque.

• kW : (continuous) – 40, 80, 120, 160, 200, 320, 450 • Voltage : 40, 80, 120: 400Vdc • 160, 200, 320, 450: 700Vdc
• RPM (Nominal): 3200
• Torque [Nm] (continuous / peak) : 128 / 225 • 257 / 450 • 398 / 675 • 530 / 900 • 660 / 1130 • 1060 / 1800 • 1580 / 2680
• Dimensions : Length (mm) : C40, C80: 550 • C120, C160, C200: 665 • C320: 915 • C450: 1030 • Weight (kg) : C40: 79 • C80: 85 • C120: 96 • C160: 104 • C200: 124 • C320: 195 • C450: 240
• Includes : Electric motor with built-in thrust bearing • Motor controller/inverter • Electronic control unit (ECU) • Electrical and water plugs • Cooling system: heat exchangers, pumps for inner and outer circle, water strainer, flow through expansion tank • Frame and engine mounts
• Country of Manufacture : Slovenia
• Price : depends on configuraiton

»» Oceanvolt website

Click »» here to Oceanvolt motors for sale in the Plugboats Market

Oceanvolt is one of the best known names in electric boat motors, especially for sailboats, and is a leader in regenerative / hydrogenerative props systems. There are standard systems available, the motors can be purchased separately, and the company can also do custom installations. Oceanvolt has both all-electric and hybrid systems, we have only included the all-electric systems here, and only the standard preconfigured systems.

Oceanvolt Inboard Systems with AX motors: 3 Models: Shaftdrive 3, Shaftdrive 5, Shaftdrive 8

• kW : (continuous) – 3.7kW, 5.3kW, 8.7kW • Voltage : 48 • Current : • HP :
• Motor Type : Synchronous permanent magnet electric • Cooling : Air
• RPM : 2400
• Dimensions : NA • Weight : 22kg, 28kg, 28kg
• Includes : Controller/battery communication kit, Hydrogeneration feature
• Available : Batteries, charger, propeller
• Country of Manufacture : Finland
• Price : $US 6,500 – 8,000

Oceanvolt Inboard Systems with AX3 motors: 2 Standard Systems: Shaftdrive 10, Shaftrdive 20 NOTE: The AX3 motors are 10kW motors that can be ‘stacked’ to create higher powered system, up to 40kW. i.e. the illustration below shows 1 X 10kW AX3 in the diagram but 2 X 10kW AX3s coupled to form a 20kW motor in the photograph .

• kW : 10kw, 20kW • Voltage : NA • Current : • HP : 20 – 60
• Motor Type : PMAC • Cooling : Liquid
• Includes : Battery, controller/battery communication kit, Hydrogeneration feature
• Price : $US 36,000 – 59,000 (includes Lithium battery pack – 13.3kWh/26.6kWh)

»» Piktronic website

Piktronik is an Austrian-Slovenian company working on the research, development and production of components for electrical vehicles (EV) and boats. Their inboards are available as standalones and also as complete systems.

Piktronik Motors : 7 Models: PMSM10, PMSM40 PMSM50 PMSM60 PMSM100 PMSM110 PMSM180

• kW : (continuous) From 10 to 180 • Voltage : From 30V to 307V • Current : From 205A to 370A • HP : From 13.6 to 245
• Motor Type : 3 – Phase  Permanent Magnet Synchronous ( PMSM ) • Cooling : Water cooled • IP :
• RPM : From 1200 to 3600
• Torque : From 80Nm – 555Nm
• Dimensions : From L: 431mm W: 220mm H: 220mm to L: 565mm W: 396 H: 396mm • Weight : From 45kg to 171kg
• Includes : See Piktronik systems below
• Country of Manufacture : Austria/Slovenia

Piktronik Systems : All of the motor power sizes above are available as complete systems. System includes:

• Display, control and battery monitoring unit 
• DC-DC converter
• Battery chargers
• Wire harness, Distribution box, battery fuses and contactors, FI-Box, Ignition switch, User guide

»» Synapseo website

Synapseo was founded by a group of passionate sailors who have a common interest in making our oceans, seas and rivers great again. They have developed the KYWAT, an adaptive in-board solution to easily replace old diesel or gasoline engines. It is available in five models with power outputs from 4kW to 20 kW. The have output shaft diameter of 25mm to 30mm and mounting brackets hat adapt to all standard engine cradles. All motors have hydrogeneration / regeneration.

Synapseo Motors : 5 Models: AE-10, AE16, AE24, AE36, AE60

• kW : 4kw, 6kW, 10kW, 16kW, 20kW • Voltage : AE-10 – AE36: 48V, AR60: 72C • HP : 10, 16, 24, 26, 60
• Dimensions (mm): • AE-10 – AE24: W: 400 L:630 H: 440, AE 36 and AE60: W: 448 L:742 H: 512
• Includes : Control panel, digital throttle, power cables, coupling, four silencing blocks.
• Country of Manufacture : France

»» TEMA website

TEMA was founded in 1989 by Branimir Ruzojcic, Dr.Sc, who is still GM of the company. Its goal was to merge academic and scientific researches and engineering practical resources for offering sophisticated industrial automation products to the market. Today TEMA offers advanced motors/generators using Permanent Magnet technology ranging from 10KW to 1500KW and offers complete electric propulsion systems for all-electric, serial hybrids and parallel hybrid boats, from small leisure yachts to large commercial boats.

TEMA Motors : 5 Models: SPM132-1, SPM132-12, SPM132-2, SPM132-22, SPM132-3

• kW : 10kW – 60kW • Voltage : 48 – 450Vdc • Current : • HP :
• Motor Type : PMAC • Cooling : Air – either natural or forced air/fan
• RPM : Nominal – 3600
• Torque : (Nominal): 70 – 205Nm
• Dimensions : • From L:275mm, H: 260mm, W: 260mm to L: 552mm, H: 260mm, W: 260mm Weight : 70 – 148kg
• Includes : motor controller, marine throttle, information display, Plug and Play easy wiring
• Country of Manufacture : Croatia

»» Thoosa USA website

The Thoosa design has been in production in Denmark since 1998, originally by ASMO Marine, which became Clean eMarine in 2012. They manufacture the AC Triton motor and the DC Thoosa line, which includes four models with power ratings from 5kW to 12kW. All are geared motors. Motor and controller are sold together, with mounting brackets. Throttles and monitors are also available from the company.

Thoosa DC Motors : 4 Models: Thoosa 5000, Thoosa 7000HT, Thoosa 9000, Thoosa 12000

• kW : (continuous) – 5kW, 7kW, 9kW, 12kW •  Voltage : Thoosa 12000 is 72V, others are 48V •  Current : (Peak) 300A – 400A •  HP : 10 – 50
• Motor Type : Axial Flux ‘Pancake’ Permanent Magnet DC •  Cooling : Air cooled
• RPM : 1080 – 1270
• Torque : (Peak) 59.5Nm – 73.3Nm
• Dimensions : NA •  Weight : (System) 37kg – 47.5kg
• Includes : Motor, controller
• Available : Throttle, battery monitor
• Country of Manufacture : Denmark / US Assembly for US models

»» Torqeedo website

Torqeedo is the world’s leading manufacturer of electric outboards. The company was founded in 2004 by Dr Christoph Ballin and Dr Friedrich Böbel when they decided they could build a better electric motor than the one on the boat Dr. Ballin had just purchased. The inboards are sold as a complete system, including batteries, and each is designed for different usage: the 1400 (RPM) models for displacement sailing with heavy boats, the 1800 (RPM) models for for planing with fast boats and the 100kW 900 for large sailing yachts and heavy displacement vessels.

Torqeedo Deep Blue Inboard Line – 25i and 50i models 4 Models: Deep Blue DB25i 1400, Deep Blue DB50i 1400, Deep Blue DB25i 1800 , Deep Blue DB50i 1800

• kW : 25i models – 27.6kW/33 Peak, 50i models – 55kW66 Peak • Voltage : 360V • Current : • HP : 25i models = 40HP, 50i models = 80 HP
• Motor Type : Permanent Magnet Synchronous (PMSM) • Cooling : Water cooled • IP :
• RPM : Model number1400 and 1800 refer to RPMs
• Torque : <280Nm – 343Nm
• Dimensions : L: 680mm W: 512mm H: 376mm • Shaft sizes : 30, 35, 40mm | 11/8,11/4” • Weight : 80kg
• Includes : Complete integrated system, including on-board touchscreen computer, batteries, shafts and propeller.

Torqeedo Deep 100kW 900

• kW : 100kW continuous • Voltage : 360V • Current : • HP : 135
• Motor Type : Permanent Magnet Synchronous (PMSM) • Cooling : Water cooled
• RPM : 900 (max)
• Torque : 1060Nm
• Dimensions : NA • Shaft sizes : 30, 35, 40mm | 11/8,11/4” • Weight : 450kg (w/o battery, including electronics)

»» WaterWorld website

WaterWorld is a joint venture undertaken by two companies, De Stille Boot, a distributor specializing in electric boating and Water World Electronics, a Dutch specialist in low voltage electronics. WWE develops and produces its own printed circuit boards and complete controllers for various markets such as the building and car industry. They have joined together to “offer boat owners and -users the ultimate joy of a quiet, calm and carefree boat ride.” The company offers four direct drive electric inboard systems, with the motor and controller in one housing with adjustable engine supports as well as monitors and other accessories.

WaterWorld Inboards : 3 Models: 4.0 i , 7.5 i , 10.0 i , 15.0 i

• kW : (continuous) – 4kW, 7.5kW, 10kW, 15kW • Voltage : 48V • Current : 92V (max), 172A, 230A • HP :
• Motor Type : Asynchronous • Cooling : Air cooled • IP :
• RPM : 1450 (max), 1350, 1450
• Torque : 27Nm, 53Nm, 66Nm
• Dimensions : (Motor and controller in frame) 4.0i: L- 558mm x W-225mm x H-221mm | 7.5i and 10.0i – L-681mm x W-290mm x H-271mm • Weight : (Motor and controller in frame) 4.0i: 39kg, 7.5i and 10.0i: 76kg
• Includes : Motor, controller, thrust bearing, relay, digital colour touch screen display, throttle
• Price : $US 3,675 – 5,500 (15.0 i tba)

Table – Searchable and Sortable

Get all the latest electric boats and boating news delivered to your mailbox!

Sign up here for the Plugboats newsletter.

IT’S FREE!

Email address:

Terms and Conditions - Privacy Policy

Better Sailing

Best and Most Reliable Marine Engines for Boats

Marine engines are the vessel’s beating heart. They produce hot water and the electricity required to spin radars, grind winches, and pull anchors. Modern marine engines are small and dependable, but they only run for a few hours at a time, which can lead to ‘standing’ issues. A typical boat will only log roughly 30 engine hours every season, which is less than your diesel car will do in a fortnight. In addition, it is rare for a marine engine to get damaged. However, they tend to corrode and need proper maintenance. It’s rare these days to come across a bad-quality marine engine. In this article, I will give some information about marine engines as well as which ones are the most reliable for sailboats. Follow me!

Characteristics of Marine Engines for Boats and Sailboats

Because the market for new marine engines is so small in comparison to car engines, there aren’t so many companies that design engines with less than 300 horsepower from the ground up. Bukh, Yanmar, and Steyr are notable companies, as they build their own basic engines using in-house components. The others are tried-and-true industrial or automotive blocks from Kubota, Mitsubishi, Volvo, and Toyota that have been ‘dressed’ with a marinized cooling system to enable them to run afloat. The quality of the marinization will have a significant impact on the engine’s reliability.

If you’re looking for the best reliable marine engines then you’re either buying a new boat and need to choose an engine, or you want to replace or enhance the one you have. In either case, you’ll be investing not only in the engine but also in its continued role in your enjoyment and safety. This means you should seek features like quick start-up, quiet operation, outstanding fuel economy, total dependability, and low-cost spares and maintenance.

Engine Power

Any motor (inboard or outboard) installed on a sailboat is an important tool that aids maneuvering. Although some competent sailors can sail efficiently without the use of power, many harbors have regulations that either prohibit the use of full sails or simply don’t allow for enough maneuvering space. And, note that docking is becoming easier with a motor that has both forward and reverse gears. While there is no exact relationship between boat length and total weight there is a general rule of thumb. For boats, up to 20ft 1-4 horsepower is a must while for boats between 20 and 30ft, 4-18 horsepower is great. Also, for boats between 30 and 40ft, the 18-34 horsepower is the way to go.

Keep in mind that in order to get your boat moving, you just need a small amount of power . However, when you’re dealing with fast currents, waves, and strong headwinds, you’ll be glad you have plenty of reserve horsepower. You should allow 3 horsepower per tonne of displacement, or 1 horsepower per foot of waterline length, as a general rule. This is general guidance with many limitations, but boat manufacturers typically over-specify the engines so that they run at lower speeds and be more economical.

When determining how much horsepower you want, there are a few factors to consider. One of the most important criteria is your location and the type of conditions you intend to sail in . Heavy seas and strong winds, which are typical of open ocean sailing, may put extra strain on your engine and, in some situations, overpower it. But, a heavier-than-needed engine would add unneeded weight when racing. So, consider buying an engine that can withstand a lot of use if you plan on sailing long distances.

How Much HP Do you Need?

The amount of power you require is proportional to the displacement of your boat’s hull. So 1 HP every 550 lb displacement and 4 HP per 2200 lb displacement. The amount of horsepower required to reach the maximum hull speed is denoted by HP. This is in ideal circumstances. You must additionally account for propellor size if you want to get it exactly properly. So, you can divide the boat’s displacement (in lbs) by 550 to find the amount of horsepower in order to efficiently propel a sailboat. Note that for most sailboats, you don’t need more than 30HP.

Generally, you need more HP for catamarans and larger boats (regardless of size) that necessitate more power. Note that engine weight and an extra step of compression in a 4-stroke engine results in less output . You will also need more HP if you have a small propeller as it tends to displace less water. If you’re sailing in the ocean , cover large distances , and deal with rough weather you will need a more powerful engine. And, gas engines have a substantially lower compression rate than diesel engines.

On the other hand, you will need less HP if you have a single hull fiberglass sailboat and bigger props as they displace more water. If you’re an occasional sailor and cover small distances you will need less HP. In addition, 2-stroke engines that are lightweight and have higher torque require less HP. And, less HP for diesel engines because they have a bigger compression rate.

Engine Size

There are a few reasons why getting the appropriate engine size is important. First and foremost, smaller engines are less expensive , thus you save money on the engine. Second, smaller engines consume far less gasoline, resulting in cost savings. Finally, smaller engines are less expensive to maintain. However, there are a few benefits to upgrading to a larger engine. More control equals more power thus it’s easier to stop the boat, in case you need to.

A bigger boat doesn’t always imply having a bigger motor. Meaning that a small power plant can be more effective than a larger one, despite varying ratings for different classes of boats. An outboard motor, on the other hand, can easily overpower a small boat and produce dangerous situations at high speeds. In general, there are differences when it comes to the engines of sailboats and motorboats.

Your engine’s physical size is a crucial issue that is closely tied to the design of your boat. Note that the engine consists of three parts. The powerhead houses the engine. The exhaust system in the midsection and the lower unit submerges when in use.

When choosing a motor, the shaft length is an important design feature to consider. A propeller with a shaft that is too short will not submerge in water, but a shaft that is too long will stretch the propellers too far. This will not only reduce the efficiency of your engine, but it will also add extra drag. When comparing models, keep your transom length in mind. When not in use, an outboard motor should be stowed in the upright position. Some of the larger motors have an automated switch that allows them to be raised out of the water, but others must be secured manually.

Two-Stroke vs Four-Stroke Engine?

Outboard engines are either two-stroke or four-stroke, with the four-strokes gaining popularity in recent years for various reasons. They’re quieter, consume less gasoline, and operate cleaner . Each power stroke in a four-stroke engine causes the piston to reciprocate four times inside the cylinder. In other words, each time the fuel combusts. Engineers reduce the length of time the intake and exhaust valves are both open by carefully engineering the camshaft. This significantly reduces the amount of unburned gasoline that departs with the exhaust stream. What’s the end result? Emissions are reduced and there are cost savings.

However, in the five-horsepower category, four-stroke engines are around 20% heavier than two-stroke engines with the same horsepower. Four-stroke engines are also more expensive, although the enhanced technology may be well worth the extra expense. You’ll want a two-stroke engine if you’re trying to save weight and money. However, if you believe you can reduce weight in other ways, a clean, quiet four-stroke without the trouble of mixing fuel could be the solution. Manufacturers are also being pushed toward four-stroke engines by environmental laws . This is because emission control standards are met by four-stroke engines.

Marinization

The standard of marinization is a key role since corrosion kills engines faster than any other sort of misuse, including unclean fuel. The heat exchanger is the most important component here. When the temperature difference between the engine and the outside water is modest, as it is when cruising in the tropics, efficiency is critical. Meaning that you’ll want to use high-quality, corrosion-resistant components that won’t need to be replaced. When looking for a new engine, you should also ask to see the spare parts price list. It’s pointless to buy a low-cost engine if the impeller is going to set you back a small fortune.

Drive Train Considerations

It’s important to note that the drive train will have an impact on the efficiency of your engine. Some owners choose to totally reposition the engine during repowering to free up more space in the boat. Switching from shaft to saildrive is another possibility. Saildrives are popular because they are simple to install from the standpoint of the boat builder. The entire unit – engine and transmission – is dropped into a specially-made cradle that is glassed into the bilge through a single large hole in the hull. And, the sea is kept out by a big rubber gaiter. The propeller works at right angles to the water, so no thrust is lost downwards, making it more efficient than a typical shaft drive. As the drive is more forward, there is usually less ‘paddle wheel’ impact, but the less prop-wash effect on the more distant rudder.

Most Reliable Marine Engines for Boats

Caterpillar c12.9 marine diesel engine.

The C12.9 did successful testing in test cells when it comes to reliability. The engine passed over 13,000 endurance hours on the water and proved its efficiency and durability. This engine has a high power density, quick acceleration, and little noise. The C12.9 received great grades for minimal noise, fast transient response, and available power throughout its testing. The C12.9 is available in two power ratings: 850 mhp at 2,300 rpm and 1,000 mhp at 2,300 rpm, both electronically controlled.

Mercury 75/90/115

Mercury introduced a new 2.1-liter outboard engine in 75, 90, and 115 horsepower models in 2015. These engines have close to the greatest displacement in their class while maintaining a low weight. In fact, at 359 pounds, it weighs 40 pounds less than the older 1.7-liter Mercury models. These engines perform smoothly, and Mercury claims that 17,000 hours of testing went into designing these outboards.

Cummins QSB 6.7

In the sport-fishing industry, the new Cummins Quantum Series QSB 6.7 with 550 horsepower is the most popular output. Cummins concentrates on noise reduction and has achieved an 80 percent decrease at idle thanks to engineering changes in their high-pressure common-rail fuel system, which is based on an in-line six-cylinder block with a new 24-valve cylinder head. This also contributes significantly to the reduction of smoke. Walker AirSep air filters are now standard, and they’re designed to reduce noise at the turbos’ air intake. The QSB 6.7 is a Tier 3 compliant power plant with a dry weight of 1,450 pounds that can be used in a variety of applications.

Cummins QSL 9

Cummins QSL engines are designed and built to provide heavy-duty performance in a variety of industries. In addition, the QSL series has superior fuel economy, enhanced cold starting capability, and produces less noise than its predecessors. The QSL9-G5 is an air-cooled turbocharged engine that is currently produced in India. The 6 cylinder engine is available in 50 Hz or 60 Hz versions, making it a versatile engine. A common-rail fuel injection system enhances engine performance, and the engine has four valves per cylinder for increased power. Lastly, note that for long-distance cruising, the fuel efficiency is excellent.

Mercury 4-stroke 3.4L V-6 AND 4.6L V-8S

The engine is available in naturally aspirated versions with outputs ranging from 175 to 300 horsepower. These are the lightest versions in their class, with Adaptive Speed Control. This is in order to keep RPM independent of load or wave conditions. The V-6 was the first of these engines to be released in 2018, and the V8 followed quickly. Mercury began supercharging these engines in 2019 to generate new Verado variants with up to 400 horsepower, extending the line even further. It’s tough to say how well these will hold up over time, but early reports from customers indicate that the models have proven to be quite reliable.

MAN R6-730 & R6-800 

With the demand for compact, space-saving engines, MAN’s in-line six-cylinder engines with horsepower outputs of 730 hp and 800 hp at 2,300 rpm are among the best engines. The R6-730 generates 730 horsepower for quick acceleration from low revolutions per minute engine speeds. This is thanks to a common-rail fuel arrangement that produces maximum torque in the 1,200rpm range. The R6-730 has a tempting horsepower-to-weight ratio for both re-powers and new builds, weighing in at around 2,870 pounds. The R6-730 does not require an external after-treatment system to meet Tier 3 emission compliance due to proven optimization of the internal combustion system.

Volvo Penta D2-50 Diesel Engine

Between the 28hp D1 and the 50hp D2, which are available in both shaft and saildrive configurations, Volvo has an odd gap in their engine lineup. The 3,000rpm of the D2 marine diesel engines is very common for this power rating. Slower rotation produces less noise and vibration in general. An inline injection is used in both series, as is the MDI electronic interface, which has had reliability issues in the past. The interface, on the other hand, makes getting NMEA data out of the engine and into your instrument network a breeze. It also makes a wide variety of stylish remote displays available. The D2 engine, however, will not operate with Volvo’s ergonomic computerized controls. Only EVC marine diesel engines with common rail injection are compatible with them.

Volvo D13-900 

The Volvo D13-900 is an in-line six with 900 horsepower that can be utilized as a conventional drive package or in conjunction with an IPS pod-drive power unit. Volvo has certainly made an impact in the maritime sector with this technology, with over 17,000 IPS systems on the water. The D-13 has a strong block with ladder-frame construction, high-pressure unit injection, and twin turbochargers with charge-air coolers, weighing in at 3,439 pounds. Volvo’s electronic control system’s engine management combines low fuel consumption and emissions with reduced vibration and noise, exceeding Tier 3 regulations.

MTU 16 V 2000 M96 Diesel Engine

The M96 is a 16-cylinder V engine that produces 2,600 horsepower at 2,300 rpm and comes with a new fuel-injection system. It also has three sequential turbochargers for improved acceleration and fuel economy. The M96 is EPA and IMO Tier 3 compliant thanks to the company’s SCR in-engine exhaust-gas treatment. The M96 is a smokeless, silent power engine with reduced vibration that is managed electronically. With the recent debut of the 92 Viking, the 2,600 hp M96’s performance qualities stand out, with the enclosed bridge variant reaching a top-end speed of 36 knots.

Yanmar 3JH40

This very popular, award-winning engine debuted in 2018 with a power output of 40hp. Its main feature is Yanmar’s common rail injection system efficiently reduces smoke and odors to almost nothing. This is owing to the diesel fuel’s more complete combustion when injected under high pressure. It also spins at a low 3,000rpm, which makes it quieter and decreases vibration than faster-spinning engines. For its engines, Yanmar has created a set of digital controls. Meaning that the VC10 and VC20 electronic throttles send data to the network, such as engine load.

Beta Marine diesel engines are built on a sturdy Kubota block and offer low-cost and excellent performance. They have a unique red color and come with a variety of installation options. This makes them ideal for repowering in confined spaces. This is a typical mechanical engine with very little electrical gimmickry, despite the fact that the design is always being refined. For its size, it has a lot of mid-range torque. Although an NMEA2000 converter is available to transfer some engine data into the network, the typical control panels are firmly analog. Also, a new digital display panel with a standard loom input and NMEA 2000 output is now available. These are good engines that are sold all around the world since they are reliable, have a lot of spare parts, and are easy to service.

Caterpillar C8.7

Caterpillar introduces its new C8.7, a six-cylinder in-line engine that replaces the C9. The C8.7 produces 650 horsepower at 2,300 rpm and weighs 2,295 pounds dry. This is thanks to a new common-rail fuel-injection system and air system. To get the boat up to speed without lagging before the turbocharger engages, the new fuel system employs a radial belt-driven supercharger in conjunction with standard turbochargers. Once up to speed, the turbo takes over for boost, and the supercharger is disengaged by an electromagnetic clutch. While remaining EPA Tier 3 compliant, this redesign minimizes smoke and provides substantial low-end torque and fuel economy. The C8.7 is well-suited to conventional drives, but it’s also designed to work with Caterpillar’s recently announced pod propulsion systems.

Solé Mini-44

Solé provides a wide range of diesel marine engines, and the Mini-44 is great for boats with a length of 32 to 39ft. This is the company’s smallest four-cylinder engine, which offers quieter operation but higher fuel consumption at the highest speeds. Despite its 42 horsepower rating, it has a lesser capacity and must work harder to accomplish it. As a result, it performs better than 38hp models. It’s a fully mechanical engine that uses cam-driven indirect fuel injection to create adequate torque in the mid-range.

The Mini-44 is an extremely versatile engine with several variations, including saildrive fittings, and an astounding range of gears. The engine’s analog data can be converted into digital signals for your NMEA 2000 network using a very expensive converter. The control panel options, however, remain decidedly analog, despite their beautiful design.

The Bottom Line

While sailing does not necessitate the use of an engine, it is a practical addition that may substantially enhance your time on the sea. Being patient and spending time searching for reliable marine engines will not only help you make the right choice but will also allow you to take advantage of a good deal. The most important criterion is to go beyond the engine’s original cost and consider the cost of spare parts, convenience of access, and maintenance. In addition, you should look for the service regime and global network of dealers in order to pick the right marine engine for your sailboat. Lastly, note that it’s improbable that the expense of a new engine installation will ever be recouped in the resale value of a used boat. Instead, you’re making a long-term investment in your enjoyment and safety.

I hope that this article will help you choose the right marine engine for your sailboat. And, that you have now understood the specs of a reliable marine engine. Wish you all safe & pleasant voyages!

Peter is the editor of Better Sailing. He has sailed for countless hours and has maintained his own boats and sailboats for years. After years of trial and error, he decided to start this website to share the knowledge.

Related Posts

The Ultimate Guide to Choosing the Best Fishing Line for Trolling

Lagoon Catamaran Review: Are Lagoon Catamarans Good?

Best Inboard Boat Engine Brands

Are O’Day Sailboats Good? A Closer Look at a Classic Brand

• Buyer's Guide
• Destinations
• Maintenance
• Sailing Info

Hit enter to search or ESC to close.

• Wishlist (0)

• Login/Register
• Manufacturers
• Exhaust Kits
• Gasket Kits
• Water Pumps
• Water Pump Service Kits
• Impellers & Service Kits
• Thermostats & Kits
• Thermostat Housing
• Thermostat Gaskets
• Inboard Alternators
• Outboard Alternators
• Alternator Brackets and Belts
• Inboard Starters
• Outboard Starters
• Inboard Ignition
• Outboard Ignition
• Exhaust Manifolds
• Exhaust Risers
• Complete Exhaust Manifold + Riser Kits
• Exhaust System Gaskets and Spacers
• Exhaust System Elbows and Plugs
• Fuel Filters & Separators
• Fuel Regulators
• Fuel Pump Service Kits
• Engine Warranty
• 3.0L 181ci 4cyl
• 5.3L 325ci DI V8
• 5.7L 350ci V8
• 6.2L 376ci DI V8
• 6.2L 376ci DI LT4
• 7.4L 454ci V8
• All Engines
• Marine Base Engines

Complete Marine Engines

• Engine Mounts
• Harmonic Balancers
• Power Steering Parts
• Pulleys and Belts
• Timing Covers
• Flywheels, Couplers and Damper Plates
• Valve Covers
• Weather Covers
• Heat Exchangers
• Oil/Gear Coolers
• Hoses and Clamps
• Tilt Trim Motors & Pumps
• Distributors, Caps, & Rotors
• Service & Diagnostic Tools
• Displays and Gauges
• Senders and Sensors
• Spark Plugs & Wires
• Wire Harnesses & Electrical System
• Exhaust Outlets and Bellows
• Catalyst Exhaust Parts
• Carburetors
• Carburetor Repair Kits
• Flame Arrestors
• Fuel Injectors
• Intake Manifolds
• Throttle Body
• Dipsticks and Fittings
• Oil Lines, Adapters, & Filters
• Velvet Drive
• Sterndrive Couplers
• Gearcase Parts
• Tilt & Trim Parts
• Transom Parts
• Key and Ignition Switches
• Seating & Accessories
• Ice Chests & Coolers
• Electronics & Accessories
• Life Jackets and Vests
• Marine Audio and Speakers
• Trolling Motors
• Jet Pump Impellers
• Mixed/Axial Pump Parts
• Jet Pump Intake Grates
• Jet Pump Drivelines & Adapters
• Outboard Fuel Systems
• Outboard Cooling Systems
• Outboard Electrical Systems
• Lower Units
• Lehr Outboards
• Marine Engines /

New 5.3L DI JetPac Engine

New 5.3L DI JetPac Engine with Catalyst Exhaust

New 5.3L DI Sterndrive EnPac Engine

New 5.3L DI V8 Sportpac with Catalyst Exhaust

New 5.3L V8 DI SportPac Engine

New 6.2L DI EnPac Engine with Catalyst Exhaust

• Complete Engine
• Mercruiser/OMC/Volvo Replacement
• Marine Power
• United Ignition Products
• Shipping Information
• Privacy Notice
• Conditions of Use
• Return Policy
• Customer info
• Shopping cart
• Compare products list
• 17506 Marine Power Industrial Park Ponchatoula, LA 70454
• [email protected]
• 985-386-2081

Log in or Sign up

You are using an out of date browser. It may not display this or other websites correctly. You should upgrade or use an alternative browser .

smallest sailboat which has an inboard engine

Discussion in ' Sailboats ' started by urisvan , Dec 29, 2008 .

urisvan Senior Member

hello, what should be the smallest size of a sailboat but still she will have an inboard engine. cheers  

ancient kayaker aka Terry Haines

I've seen a sailing kayak equipped with an electric trolling motor.  

Doug Lord Guest

I had a 20' motorsailer with a 15hp yanmar diesel....700 mile range under power.  

masalai masalai

I can remember 14 to 16 ft double ender? lap-strake planked heavy rowing boats fitted with a little petrol one cylinder salt water cooled inboard operating in the "sheltered waters of what is now the Gold Coast around the 50's to haul nets out from the beach and everyone strolling along would help to haul the net in and get a fish or two as thanks for their help, also some were later available as hire boats for fishing/crabbing in the rivers....  

timothy22 Junior Member

In the '70s I had an 18' lateen rigged flat-bottomed, long keel, double ended, decked over weekender with a 5hp Kermath. It had a standing well aft, and I pitched a pup tent on deck. They loved it in Tarpon Springs!  

Code: I had a 20' motorsailer with a 15hp yanmar diesel....700 mile range under power. thanks for different kind of examples. they are both nice. but i am espacially interested in coastal cruisers. please send more examples. doug lord, that sounds nice. what was the model of your boat? cheers  

urisvan said: ↑ Code: I had a 20' motorsailer with a 15hp yanmar diesel....700 mile range under power. thanks for different kind of examples. they are both nice. but i am espacially interested in coastal cruisers. please send more examples. doug lord, that sounds nice. what was the model of your boat? cheers Click to expand...

thanks, what i had in my mind is a sailboat, capable of going in heavy seas, maybe not in the ocean, but in agean sea, where there are high winds sometimes(not very big waves).  

look at something like the smaller Lombardini 2 cyl inboard marinised engines - fairly light and seem quite popular in Europe.... 500cc and 700cc diesels....  

mattotoole Senior Member

I've read that a few Cape Dory Typhoons came with inboards, but I've never seen one. Can anyone confirm (or deny) this?  

PAR Yacht Designer/Builder

A Flica, would fit your request nicely. 20' on deck, standing headroom (5' 11"), 8' beam, 3' 3" draft and displaces about 3 tons. A good little sea boat by Pacific Seacraft She's rough water capable and would be fairly comfortable, considering how short she is.  

Hey, that is quite cute....  

peterBUILT New Member

Look at: International Folk Boat, or Cheoy Lee Frisco flyier.  

keith66 Senior Member

Or there is the Anderson 22, Oliver Lee design, fast & seaworthy with lifting keel, mine has an RCA Dolphin 12 HP petrol inboard thats like having a smooth turbine under the deck. http://anderson22class.co.uk/  

• Advertisement:

JotM Junior Member

In order to round up some more ideas to chew on: the North Beach 24 or the Wadkrabber Both a bit longer, but able seaboats. If I turn back to the original question, which I interpreted like "is there a minimum size for a boat to carry an inboard engine?", as a mechanical engineer I would say "No". One could probably use the smallest air cooled single cylinder diesel engines (like e.g. the Lombardini 15LD225, the Mitsubishi L2E or the Yanmar L48V) fitted out for a marine environment. At a weight of 25-35 kg you should even be able to mount that in a small beachboat. (with a max. power < 5 HP your boat shouldn't be a whole lot bigger ) Cheers.  

Home build Sailboat Design

Can someone help me identify this 1977, 7.7m sailboat in Europe?

fishing sailboat

Sailboat Design and Operation and Improvements to

Rowboat->sailboat conversion

Identify sailboat designer/builder?

1950's Raven sailboat (Cold molded hull questions)

Help me find a boat: 26ft planing centerboard wood sailboat?

Re-rigging a small sailboat (Luger Southwind 21 to Catalina 22)

Design refinement in small sailboats that aren't raced?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Please verify you are a human

Access to this page has been denied because we believe you are using automation tools to browse the website.

This may happen as a result of the following:

• Javascript is disabled or blocked by an extension (ad blockers for example)
• Your browser does not support cookies

Please make sure that Javascript and cookies are enabled on your browser and that you are not blocking them from loading.

Reference ID: 694728d8-6d14-11ef-894a-3a4f42a4cef7

Powered by PerimeterX , Inc.