Stern Drive Packages


The most common type of propulsion package that MarineDiesel sells is with stern drives as the propulsion type.


  1. Stern drives are highly versatile. They can be used in just about any mission or application.
  2. Stern drives are generally inexpensive.
  3. Stern drives can provide a very high top speed.
  4. Stern drives are generally easy to maintain or replace.
  5. Stern drives are manueverable at slower speeds.
  6. Gearboxes are usually integrated into the drive unit.

MarineDiesel packages two brands of stern drive with its’ engines, in different situations:

On recreational vessels, we can provide Mercury Bravo drives. Mercury Bravo drives give good performance while being inexpensive. However, they are typically not designed for commercial or heavy use. This is why we typically only recommend them on vessels that will operate under 200 hours per year. Bravo drives are limited to 400 hp applications (sometimes, depending on the vessel, 450 hp will work).

On commercial or military vessels, we provide Konrad stern drives. Konrad stern drives are engineered to take the punishment and abuse that commercial or military users require. With a MTBO of 2,500 hours, Konrad drives give top performance and reliability. Our entire engine range will work with Konrad drives.

When are other propulsion types more appropriate?

  1. On vessels requiring more than 500 hp.
  2. Low draft situations.
  3. Vessels over 14t displacement.

As with the other propulsion types, proper calculations are a must and require proper vessel information.

If you would like a complete stern drive propulsion package quoted with your engines, contact your local MarineDiesel distributor today for a custom quote, or contact us directly for assistance.





Surface Drive Propulsion Packages


Continuing from yesterday’s article about propulsion packages, there is one type of propulsion that will always provide the highest top speed on any vessel: Surface drives.

MarineDiesel has teamed up with France Helices to offer the France Helices SDS surface drives to our customers, as a package with our engines.

Of all of the propulsion types available in the market, surface drives will give the highest top speed and, in the case of articulated surface drives, the greatest level of control and maneuverability on high speed or high performance vessels. In layman’s terms, surface drives use the cavitation produced by the propellers as thrust, while minimizing drag, thus ensuring extremely high top speeds. They are designed to force a vessel to plane quickly, and efficiently. Of course, on high speed vessels, proper calculations are essential to achieving the required performance levels. France Helices specialize in designing propellers specifically intended to give required performance levels. In other words, the drives are customized to the vessel, and not the vessel customized to the propulsion.

When are surface drives appropriate?

  1. Any vessels required to achieve top speeds over 50 knots (In some cases, surface drives are the only way to achieve these speeds).
  2. Vessels that will operate in shallow draft areas.
  3. Vessels that will operate in dirty or polluted water.
  4. Vessels that require extremely high levels of maneuverability, crash stop, or acceleration.
  5. Vessels that will operate in rough seas.

When are surface drives not the best choice?

  1. On vessels that will operate at speeds below 30 knots a substantial amount of the time.
  2. On vessels used for boarding (like pilot boats).
  3. On vessels that will operate with people in the water nearby (rescue craft, dive boats).
  4. On vessels that are overweight by design (large displacement variations).
  5. On vessels that have displacement or semi-displacement hulls.

On surface drive equipped vessels, the calculations can be somewhat involved, requiring a substantial amount of information on the vessel. Visit the France Helices website for more information.

If you would like a quote on a performance package with MarineDiesel engines and surface drives, contact your local MarineDiesel distributor or dealer today, or MarineDiesel directly, for a customized quote.







Water Jet Propulsion Packages


MarineDiesel packages its’ engines with a wide variety of different propulsion options, whether conventional propeller, surface drives for extremely fast vessels, stern drives, or water jets. Our customers often like the “One Stop Shop” ability, and we have made arrangements to provide these packages at full warranty.

As with any propulsion method, proper calculations are essential to achieving required vessel performance. Ever drive and propulsion maker has their own calculation programs for their drive types, and it is important that required vessel information is correctly provided to ensure the proper matching of engine to drive.

Water jets have some distinct advantages over other types of propulsion systems:

  1. Safety is the most important advantage of water jets. Without propellers spinning in the water, vessels are, inherently, much safer. The propulsion arises from an impeller, located within the drive unit. This makes water jets ideal for ski boats, rescue craft, lifeboats, dive boats, or any other vessel that will be operating in close proximity to people.
  2. Very often, water jets can be operated without a gearbox (this is usually dependent on vessel displacement), thus saving money on installation.
  3. Most water jets are relatively easy to maintain, with the primary maintenance required being the clearing of the tunnel and intakes, along with the inspection of the impeller.
  4. Water jets have good maneuvering capability at slower speeds.
  5. Water jets can provide a high top speed, though, in most cases, lower than surface drives or stern drives. However, water jets do not face the same displacement limits as other propulsion types.

MarineDiesel primarily packages our engines with two brands of water jets (Though our engines will work with any brand of jet, as long as the size is correct):

Alamarin, made in Finland, on smaller vessels.

Doen, made in Australia, on larger vessels.

Both of these brands have proven to be reliable and easy to maintain over their respective life cycles. Additionally, we can sometimes offer Hamilton, Kamewa, or other brands of water jet through our distribution and dealer network (Most of our distributors represent multiple brands of marine equipment).

For your next project, contact your local MarineDiesel distributor or MarineDiesel directly for a customized quote on an engine and propulsion package.




Who is NIRA?


MarineDiesel’s VGT Series of marine engines goes against the Bosch mold in the industry when it comes to the electronics and ECU with which the engine is equipped. Why?

The simple answer is that there are other control units on the market that are more adaptable, more reliable, and offer far more flexibility. We use a NIRA ECU with our VGT engines, and we do so because this ECU lets us “customize”, to customer requirements, the performance of the engine. We can program multiple engine MAPs into the ECU, and it allows an operator to change, via a switch, how the engine performs (ie: on a military boat, one MAP for patrol and a different MAP for boarding.

Who is NIRA?

NIRA is NIRA Dynamics AB, a Swedish company that specializes in monitoring and electronic control systems.

From the NIRA Website

A Swedish expert company focusing on innovative software solutions for vehicles

NIRA Dynamics was founded in 2001 and is located in Mjärdevi Science Park in Linköping, Sweden, from where we support customers and partners worldwide.


NIRA Dynamics is developing unique sensor fusion based systems for different vehicle applications that utilize the potential in the sensor fusion idea to improve the performance, reduce the system cost and at the same time, increase the customer value. Through close collaborations with world-class research groups at Linköpings universitet, Sweden, and Chalmers University of Technology, Sweden, NIRA Dynamics is constantly in touch with the research frontier in these and other areas where sensor fusion and other types of signal processing are employed.

Sensor Fusion

Sensor fusion, or sensor data fusion, can be described as using information from several different physical sensors to compute new, virtual sensor signals. The virtual sensors can in principle be of two different types:

  • Improved versions of physical sensor signals, or
  • So-called ‘soft sensors’ or virtual sensors that have no direct physical counterpart.

In both cases sensor fusion adds value, not cost.


By using technologically advanced components produced by companies such as NIRA, MarineDiesel ensures that our customers get the high levels of performance that they require.



When should you repower your boat?


On this blog, we often mention MarineDiesel engines as being suitable for repowering a variety of different vessels and applications. Indeed, perhaps 20% of our new engine orders are destined for repowering or retrofitting projects.

When should you decide that a repower if preferable to simply rebuilding the engine?

This is often not an easy decision to make. Most diesel engines can be rebuilt three or four times without any problems. It is important to note, however, that every time that an engine is rebuilt, no matter how competently, there will always be a degradation in engine performance. This should be a concern when deciding, “Should I rebuild?” or “Should I replace?”

Suppose your engine has never been rebuilt before. It has only been used in fresh water. It is still delivering an appropriate amount of horsepower, but starts sluggishly and you are needing to replace different components more often as they wear out. In this scenario, rebuilding the engine is probably a good bet. It is far less expensive than buying new, and it is just simply starting to near the point of requiring a complete overhaul.

In a different scenario, assume an engine has had extremely heavy use, always in salt water, and under a wide variety of throttle settings. The engine has had some hard wear. Symptoms start going beyond merely sluggish starting and may include smoke, noticeable decreases in power, and high increases in the number of spare parts required to keep it operating. The engine may have been rebuilt one or more times previously. This engine is a good candidate for replacement, and repowering.

Ultimately, the decision usually comes down to cost. Rebuilding an engine, on average, costs approximately 60% of the cost of buying new, assuming the use of OEM parts and keeping in mind the wide variation in labor costs around the world. Additionally, unless being replaced with the exact same engine make and model, new mounts, couplings, shafts, drives, and possibly propellers will also need replacement.

It is also important to note that engine technology has progressed at nearly light speed over the past two decades. In particular, emissions requirements have led to engines that are smaller, more powerful, and far more fuel efficient than even identical brands were twenty years ago.

Indeed, fuel efficiency should never be neglected in making this decision. Gains and operating cost reductions from more fuel efficient operation can easily cover the cost of repowering your vessel, as can the reduced maintenance that owners of new engines will experience.

If you would like a custom quote on your repowering project, contact your local MarineDiesel distributor today, or contact us for a free, no-obligation proposal.




Maintenance Tip of the Week – Batteries 02/23/2015


Maintenance Tip of the Week – Batteries

Always check your battery connections and cables for corrosion. Corrosion can start and progress quickly and weak cables lead to electrical system problems.


Spring is coming. How to prepare your engine after winter storage.


Last fall, we wrote an article related to preparing your engine for winter storage. Since the Spring season is fast approaching, we have also detailed below the procedures for getting your engine reasy for the warm weather after storage all winter.

Procedures after winter storage

• Exhaust System

Remove all winter-storage-seals from exhaust and intake system.

• Electrical System

Reconnect the fully charged battery/batteries and tighten/lubricate the connectors. Check the condition of the serpentine drive system belt; replace if worn or dry.

• Cooling system

Recheck that all hoses and fittings in the raw-water system are connected and replace the impeller (be careful not to scuff the impeller, use grease). Prime the raw-water system to prevent overheating of the impeller at start-up.

• Air filter

Replace with new filter unit..

• Start-up

Starting procedure

Before starting the engine always check the oil and coolant level. Also inspect that no leaks on oil-, fuel- or cooling systems are evident.
1. Make sure gear is in neutral and that throttle is in idling position.

2. Turn ignition key to the ON position and wait for glow light to stop. This allows the automatic glow system to glow it’s first sequence.

Warning: DO NOT USE STARTING AIDS SUCH AS STARTING GAS; ETHER OR OTHER. (this will void any warranty.)

3. Turn the ignition key to the CRANK position to start the engine. If the engine doesn’t
start in 15 seconds, wait for 30 seconds and go back to step 2. As soon as the engine starts, let it run at idle while checking oil pressure and volt reading. It’s not unusual with smoke from the exhaust system just after start-up but this will stop once the engine reaches operating temperature. Glow system will automatically afterglow. Recommended cruising rpm for all Marinediesel engines is 2700-3200rpm although the maximum rated effect is at a higher rpm. It is necessary to choose a propeller that will allow the engine to reach maximum engine rpm at WOT to not inflict unnecessary load on the engine, which could effect longevity and void warranty. Do not exceed maximum recommended engine rpm as the pump reduces the amount of injected diesel after this rpm and engine power drops quickly.

Check for leakage of oil, fuel and water. Also check the oil level on the dipstick, if necessary fill up with oil. Let the engine idle up to operating temperature before usage or shutdown. When the operating temperature is achieved, again check for leaking fluids. It is always good to mix approx 1% two-stroke oil into the fuel tank once a year to give the fuel system added lubrication.



恭喜发财 (Happy New Year!)


MarineDiesel extends our best New Year wishes to our customers in Asia! We wish you all a happy and prosperous year ahead!

Always check your serial number


Engines occasionally have mechanical problems. They all do. Often, when customers or distributors contact MarineDiesel for service or spare parts, the first thing we will ask, even before the problem, is for the engine’s serial number.

The serial number of the engine is always located on a metal tag on middle of the starboard  side of the engine (right side on non-marine or industrial engines). The serial number will be in the following format MD-XXX######, with six digits after the “XXX”.

Why do we ask for the serial number? Several reasons:

  1. Often, there have been service advisories, component upgrades, or changes to the design of the engine that were made after it was built. The serial number is logged at the time the engine is manufactured, and we instantly know what, if any, changes were made since that time.
  2. Warranty issues always require a serial number. If we have warranty repairs, we need to track them based on the date of manufacture.
  3. We need to verify the specific engine model. Though perhaps 80% of the components are compatible between engine models, around 20% are non-compatible.
  4. We need to check the version of the ECU software and whether any customizations were made.





Join MarineDiesel this year in Portugal at the HSBO Forum




Once again, MarineDiesel will be exhibiting and participating in the HSBO Forum, this year being help in Lisbon, Portugal. MarineDiesel has traditionally been a supporter of HSBO and Ullman, and we are excited to continue that support this year.

One of the things that makes the HSBO Forum very unique is the fact that vessels are available for sea trialing during the conference. MarineDiesel has always encouraged customers and interested parties to experience the performance and low noise and vibration levels for themselves. In fact, we believe that once you try our engines out, on the water, in a bonafide vessel, that the engines sell themselves (They really do!)

HSBO takes place from May 4 – 6, at the Champalimaud Foundation Conference Center in the Algés Marina in Lisbon, Portugal.

It offers a mixture of theory and practice, with world-class presentations, social networking events and boat trials of up to 30 of the best boats built, at full speed at sea, as well as literate discussions relating to all aspects of boat operations. Sharing of practical experiences and demonstrations of various new equipment and routines are key elements of HSBO Forum. Delegates include leaders of many professional agencies operating high-speed boats around the world, procurement & acquisitions officials, boat operators, naval architects, engineers, scientists and boat builders.

Attendance at HSBO is by INVITATION ONLY. If you wish to attend, you need to visit the HSBO website today and request an invitation. This conference should be considered a “must” for all who are in the high speed boat industry.