Alternator Power Onboard



MarineDiesel provides power for a wide range of vessels, but one vessel type that is very, very common is RHIBs, or Rigid Hull Inflatable Boats.

RHIBS are typically high performance and operate at high speeds, mainly in military applications, but also in a variety of applications ranging from rescue to tenders for yachts.

One aspect about RHIBs that is important is that they are very light weight. Space is often cramped, with not much room for engines or even an engine compartment. Engine compartments on many of these vessels are typically very tight, with little room for gensets.

But what if you need a power supply onboard?

MarineDiesel’s solution is that we can mount additional alternators to the engines to give up to 259 amps of 12V or 24V power onboard, based on customer requirements.

We have several different types of alternators which we use, some more expensive than others, but overall, on cramped vessels, this power solution may be the only way to get a reliable power source onboard.

Should your project require this type of capability, please ask your MarineDiesel distributor to provide you a quote (Make certain you let them know how much power you require… More power requires more alternator).


My engine is now non-compliant for emissions. What can I do?



Fortunately, for most MarineDiesel customers, the emissions regulations coming soon will impact large vessels, mostly. The vast majority of our customer vessels are under the 30 ton limit (And our engines are Tier IV, so the expense of ULSD is their biggest concern). However, we still receive some inquiries asking, “What do I do?”

The answer is, unfortunately, complicated. Different emissions are controlled by different methods. SOx, in particular, is often the biggest concern, given the added expense.

With the size of our engines, replacement is often the most cost efficient method. On container ships, with power measured in mW, the story is different. Those engines can cost into the millions of Euro. But, to simplify things:

1. SOx can be removed by scrubbing (using chemical treatment) or ULSD. Those are the options. Scrubbing is not only expensive, but requires a lot of space for the scrubbers themselves. Not really practical when dealing with a 500 hp engine.

2. PM and Smoke can be controlled by filtration.

3. NOx can be controlled by the use of an SCR (Selective Catalytic Reduction). A SCR is, essentially, a mesh in which a chemical (usually urea) “washes” over a catalyst that makes the Nitrogen atoms “stick” to the catalyst. Expensive equipment, though a few MarineDiesel customers have goner this route rather than replacement, usually in situations where our engines are used as auxilliary engines in multi-engine installations.

CO cannot be controlled. CO2 can be controlled by scrubbing, to a certain extent, but on small engines, this is not really practical.







Green Engine Regulations and Development



Whether you agree with the premise of climate change or not, tighter emissions controls are coming, and engine users around the world will soon be forced to ensure that their engines are in compliance with new, stricter emissions regulations. These regulations impact not only the marine market, but all industrial, on road vehicles, and off road vehicles.

The next batch of regulations coming for the marine industry will come into effect in 2016, with further reductions coming in 2020.

On this blog, we have published the following resources for your reference, that we hope you find useful.

Emissions Page

Links Page

Yes, the regulations are complex. Yes, they can be confusing. In general, the following organizations make and enforce the regulations:

  • IMO (Global Shipping)
  • EU (Europe)
  • EPA (USA)
  • CARB (California)

Though there is quite a lot of overlap in the limits, the IMO has tried to at least make the rules somewhat consistent. The specific regulation regarding maritime emissions is known as MARPOL Annex VI.

Generally, there are a number of Emissions Control Areas (ECAs) that govern the maximum amount of emissions that may be emitted. The current ECAs are:

  • North America, including all of the USA, all of Canada, and large parts of the Caribbean
  • Most of Europe (Stricter regulations in areas like Bodensee)
  • The Black Sea
  • The Arctic (Separate treaty)
  • The Antarctic (Separate treaty)

ECA Boundaries

seca map

Additionally, engines are classed based on the tier of environmental regulations with which they comply. All MarineDiesel VGT engines have tested for Tier IV and are awaiting certificate issuance in 2014. Current Tier IV regulations are listed HERE.

If your vessel will operate in any of the ECAs, your engines must be in compliance.

The following emissions are covered under the regulations:

CO2 (Carbon Dioxide)

NOx (Nitrogen Oxide)

PM (Particulate Matter)

CO (Carbon Monoxide)

Smoke (as a percentage of emissions)

The above list of emissions are products of combustion. They can be removed or reduced through engineering, aftermarket treatment options, or a combination of methods. All MarineDiesel VGT engines are in compliance with the above (no after treatment required). Additional regulations apply to:

SOx (Sulphur Oxide)

SOx is a product of the fuel used. All diesel fuel has some level of SOx present. The use of Ultra Low Sulphur Diesel (ULSD) can control SOx emissions.

All of these regulations are controversial to one extent or another, in particular SOx regulations.


The answer is cost. ULSD is over twice the cost of lower grades of diesel (Due to more refining, politics, and other reasons), and since vessel operations have fuel as their biggest operating expense, by far, this has a huge impact on operating costs. In fact, within the ECAs, lower grades of fuel than ULSD are increasingly unavailable.

Our posting tomorrow will address your options if you own a non-compliant, older engine.






Maintenance Tip of the Week – Overfill 09/15/2014

Maintenance Tip of the Week:

Overfilling oil causes several issues: Wasted oil and its’ additional cost, excessive wear on gaskets and seals, and, most problematic, oil may get blown into the intake manifold, and into the cylinders, where it will foam and lose its’ ability to lubricate.





Who competes with MarineDiesel? Why should you care?



No doubt about it… The diesel engine market is highly competitive.

How are MarineDiesel engines different than those manufactured by our competitors?

How do we distinguish ourselves?

First off, we prefer to let our products speak for themselves. This article in no way is intended to speak badly about our competition. In fact, we are often the first to recommend a competing product if one of our products is not a good match to a customer’s project. In other words, if a competitor makes a product that is better suited to a particular vessel, we will recommend it over our own.

There are many factors that go into the decision as to which engine to choose. Every company does at least one thing very, very well. MarineDiesel tends to focus our products on one particular market segment: Small, high performance vessels. Though the competitors listed below all produce engines that may compete, some are better suited than others. Sometimes, price is the only determinant, and that is fine. We understand the marine business, and sometimes there are unrealistic demands made, or sacrifices made in the name of price. We are neither the cheapest in the market, nor the most expensive. We do, however, believe that we deliver the greatest value engines to our market segment. Every engine maker in the world has market segments or geographical regions where they have a distinct advantage.

In general, MarineDiesel competes closely with the four manufacturers listed below. Why should you care? As stated above, we believe that our products stand on their own merit. So we are even willing to tell you who our competitors are… Check them out and judge for yourself:

1. Volvo Penta: Volvo Penta makes very good quality engines, no doubt about it. They are also a very large company that can be somewhat inflexible when it comes to customization or highly specialized applications. Featuring a fairly robust service network, Volvo Penta is often very competitive in the leisure or recreational markets. This is how the vast majority of their engines are rated and they perform well in that market. We compete with the D6 and D9 series.

2. Yanmar: Yanmar make very reliable six cylinder engines, and they have a very good, well deserved, reputation in the recreational engine market. Though their service network is neither as large as some of the others, they tend to provide very good sales and service. Like Volvo Penta, customization can be difficult, and their engines are very seldom rated for any use other than recreational.

3. Cummins: Cummins has a long and storied history, and their extensive sales and service network is known for good service. Their current QSB 5.9 series competes very closely with MarineDiesel. This is the only competitor that can rate engines as anything other than recreational use. They are often very competitive in price and often are willing to customize.

4. FPT: FPT is the current incarnation of Iveco, and we are competing with them more and more often. Their service network is not as robust, with large regions of the world excluded. Their N70 model competes with our engines on some projects, and they are often a very competitive price.

So, how do we distinguish ourselves in a very crowded market?

  1. We manufacture the only V configuration engine in this market. All of the rest are inline six cylinder engines, whereas ours are all V-8.
  2. We manufacture the lightest marine engines in the market, with highest power to weight ratio.
  3. We manufacture the smallest (in terms of physical size) engines in the market.
  4. We are the only engine that is NEVER rated for simple recreational use. Medium commercial is our lowest rating.
  5. We are the only company in the market that can easily, and quickly, customize an engine, from rating to color of its’ paint. Being a much smaller company often carries advantages.

So, which engine is right for you? It really depends on your application and how the engine will be used. MarineDiesel’s customers appreciate our flexibility, performance, and having an option.





10 quickest ways to ruin your diesel engine



MarineDiesel prides itself on manufacturing engines of the highest quality, yet, sometimes we see things that make us scratch our heads and say, “What were they thinking?”

So, without further adieu, below is the list of ten things that we guarantee will kill your diesel engine as fast as a stick of dynamite:

  1. Not changing fuel filters, or, even worse, running without filters. (“But hey! Filters get EXPENSIVE”. Seriously, have you SEEN the fuel in Nigeria?)
  2. Not following engine break-in procedure
  3. Not changing air filters
  4. Not changing oil filters
  5. Not letting the engine warm up
  6. Not checking for leaks (at least until there is no oil left)
  7. Full throttle, 100% of the time
  8. Not starting the engine regularly. Sludge is never a good thing. (see below)
  9. Not checking fuel quality (Condensation? Nah… Not on this boat)
  10. Not checking temperatures. (You think that plastic bag blocking the strainer might cause overheating?)

BONUS: If you think that duct tape makes a permanent repair, no further comment is necessary.


Fuel Injectors – OEM or Aftermarket?



Perhaps the most critical component of your diesel engine is the fuel injectors. These parts are, admittedly, expensive, and not particularly easy to replace.

Especially when operated in areas with dirty or bad fuel, clogged injectors create many problems with your engine, not least of which is loss of performance. Though the standard sizes of injectors are the same per engine block, the materials from which they are made is not standardized. For marine use, fuel injectors are made to withstand corrosion and the marine climate. This is where you can run into problems when replacing injectors with cheaper, aftermarket parts. Since our engines use a Duramax block, and these are standardized bv GM for automotive and truck use, there are many aftermarket injector options on the market.

Should you use these?

Our answer, generally, is “No”. MarineDiesel genuine spare parts (“GSP”) are designed for the specific use where the engines will be used. On marine engines, these fuel injectors will resist corrosion and give a long life cycle. Cheaper aftermarket parts offer no such guarantees.

Additionally, diagnosing injector problems is technical, normally requiring dealer service unless the customer has the facilities necessary to diagnose the problem. The fuel in common rail engines is under tremendous pressure, and specialized testing facilities are required to determine if an injector is faulty.




Choose the right prop



When vessels don’t perform, or an owner wishes to improve performance, one of the easiest ways to drastically change the vessel’s overall performance is by changing the propeller. But how do you do that without messing things up?

Though we are an engine manufacturer, we sell many engines complete with the customer’s desired propulsion as a package. In these instances, we usually ask our partners or the propulsion makers to make calculations.

Critical to performance is the proper calculations. Any major propeller maker can make calculations for their props. It is a balance between hull, engine, and propeller. For propellers, you can always contact our partner, France Helices, though any manufacturer that makes quality can design you a good prop.

In order to make calculations, a minimum of information is required: Vessel specs (LOA, LWL, Beam, Disp, etc.), Engine specs, and at minimum, a GA drawing of the hull since these have different efficiencies (or, items like foils or spray rails can alter performance).

There are several important factors that impact a propeller design:

1. Diameter

2. Pitch (how the blades are “twisted”)

3. Skew (the degree of transverse offset of the blade from the hub)

4. Rake (The degree of angle of the blade from 90 degrees perpendicular to the center of the hub)

5. Camber (sometimes referred to as the “cup”)

6. Blade Thickness (Thicker blades result in less vibration, but can give greater cavitation).

If the propeller is not designed correctly, or is installed with incorrect parameters, then cavitation, which causes prop damage, engine strain, and gearbox strain among other things, is sure to result.

This is why you should always input bona-fide data into any calculations: Especially the correct displacement, which is the most common error made in calculations.

Should you not have a propeller manufacturer make calculations, there are several tools online:

From (Requires Membership)

I-Phone App from Roth Company (Inexpensive)



MarineDiesel Poll: Dealer Service



This week’s MarineDiesel user poll relates to dealer service:

[socialpoll id=”2214464″]



Maintenance Tip of the Week – ECU 09/08/2014

Maintenance Tip of the Week – 09/08/2014

The engine’s ECU can misinterpret excessive torsional vibration as an engine misfire, and this condition is commonly associated with excessive wear on the coupling bolts, flywheel bolts, or the engine mounts. These connectors should all be inspected thoroughly and replaced.