FRP – Is it the right service option for my business?

Vessel downtime is a bottom line killer. The costs of a vessel being out of service can far exceed the cost of maintenance or simply replacing an engine should failure occur.

Though Marinediesel are experts in manufacturing engines for heavy use and long life cycles, our engines occasionally break down and require repair.

The best way to minimize the cost of downtime on vessels with extremely critical operating schedules is Marinediesel’s FRP – Factory Replacement Program. All Marinediesel distributors are fully trained and can offer these service agreements.

The FRP ensures that should mechanical failure occur, the quickest possible maintenance will be immediately in force.

How does the program work?

  1. The customer contracts in advance with Marinediesel to provide a spare engine on loan at the MTBO.
  2. The existing engine is removed by the local distributor and sent to the factory for overhaul.
  3. When complete, the newly overhauled engine is returned to the customer and installed by the distributor.

What are the advantages of this type of contract?

  1. As the manufacturer, Marinediesel is well-positioned and equipped to completely overhaul the engine, quickly, correctly, and to “as new” standards.
  2. Vessel downtime is minimized. A spare is kept by the distributor locally. “Pop it out and drop it in”. Quickly, and with no bottom line impact.
  3. Maintenance costs are known in advance and kept under control. No surprises for unexpected “rush” or “express” services.
  4. While the engine is being overhauled, the latest upgrades can be performed at the same time.

If you are interested in FRP on your next project, simply contact Marinediesel or your local distributor for a quote.

At what point does saving money become a project?

We all want to save money. Sure, it is human nature to spend the least, but get the most. However, there is the old idiom about being “Penny wise, but Pound foolish”, often incorrectly attributed to Benjamin Franklin, that often applies when comparing options.

We once had a suspiciously large parts order from a new, unknown customer. When the parts department received the order, they were perplexed: When did we sell an engine to these guys?

They combed through our accounts history and found nothing. What was going on?

It turns out that the customer had been given a GM engine block on the aftermarket (an old GM truck engine) and was trying to marinize it himself to use it on his boat. There are a number of different reasons why this is not a good idea for the average home mechanic, no matter how experienced or no matter how good his mechanical aptitude:

  • Most workshops lack the facilities for proper marinization.
  • You generally cannot use automotive parts in a marine engine, due to corrosion issues.
  • Marinization is a highly technical process. Without experience, the process can quickly become complicated and expensive.
  • Engines perform differently on the water than on land. The power and torque curves are completely different, and on an electronic engine, significant software knowledge is required.
  • Modern emissions requirements are tricky. In some locations, operating a vessel without certified emissions is illegal. It is very difficult to meet emissions requirements without the proper testing facilities.


Most of all….

Marinediesel, as a manufacturer, has certain economies of scale when purchasing components. Quite simply, when you buy thousands of injectors, you pay much less than when you are buying two. Additionally, though it really isn’t a secret, most manufacturers make most of their profit from spare parts and service, rather than from the sale of the engine. That is why there is usually a big difference in markup on spares, but very little difference in price between similar engines (ie. Volvo Penta D6 vs Marinediesel VGT 400).

In the end, he was a little shocked that refurbishing his old engine would end up costing almost as much as a new engine. We finally convinced him that he would spend so much time and money that he really would save very little in the end, and most likely end up spending more. A project, indeed…

Wiring Color Coding

When you take a look at an engine, it can easily resemble a mass of wires and cables. However, one of the tools provided to assist in maintenance is the color coding of wiring. Wiring is standardized according to SAE regulations, of which Marinediesel is compliant. However, color codes between manufacturers may vary slightly from make to make.

Marine wiring is twisted pair, shielded, to minimize interference (EMF). It is required to be both oil resistant and able to withstand heat of at least 75° C.

There are a few minor differences between marine wiring and wiring intended for land vehicles, normally the fact that vessels require a higher gauge and extra moisture resistance due to their environment.

So, what are the color codes?

Marinediesel has numerous charts listing the color codes to specific engine components in our electrical manual, available for download.

Though there is some variation, as mentioned, between manufacturers, there are some general consistencies:

marine wire


Fitting the square peg into the round hole

Marinediesel engines are compact. How compact?

Well, our VGT Series of engines are take up a mere 0.625 cubic meters of space.

Compare this to our competition (taken from the product data sheets produced by the manufacturers):

Yanmar 6LY3 – 0.926 cubic meters

Cummins QSB 5.9 – 0.762 cubic meters

Cummins QSB 6.7 – 0.856 cubic meters

Volvo D6 – 0.699 cubic meters

FPT N60 – 0.896 cubic meters

With an engine as compact as the VGT Series, and as flexible with remote component location (like the intercooler or starter), the VGT Series will fit into cramped engine compartments, such as those found on RHIBs or small patrol boats.

Additionally, smaller size translates into a much lighter engine, a critical feature when discussing vessels that will exceed 40, 50, 60, or even 70 knots in speed.

With this size and space differential, using one of our competitors’ larger engines truly is a case of trying to fit the square peg into the round hole.

What is J1939 protocol, and why should you care?

When looking at different engines, you may encounter the term J1939, and this term is important, but why?

J1939 is the proprietary name of the protocol used by engine manufacturers for vehicles. Much like spoken languages, such as Chinese or English, J1939 Protocol refers to the language that the engine “speaks”. The ECU of the engine takes the signals sent by the engine sensors and either makes adjustments (as in fuel to air mixture) or communicates that information, either to a display, or to a software program.

Much like language in humans requires listening and speaking, an engine protocol requires both receiving information and communicating that information. So, what is J1939. J1939 is the SAE standard that engine manufacturers typically use to ensure that the engine is in compliance with industry standards. Since the majority of marine engines are derived from automobile, truck, or other engines, this protocol is largely standard. Additionally, there are various ISO standards that are also required, often mandated by law. However, J1939 is not mandated. It has simply become the overall standard that most engine makers use.

Why is this? In short, nothing legally requires an engine maker to use the J1939 protocol, but should an engine maker not use J1939, they would face major problems with component compatibility (like ECUs), monitoring systems, and even from manufacturers of gauges. Additionally, since the maintenance shops at marinas, government, and commercial operators are equipped to deal with J1939, end user maintenance becomes much easier and cheaper when standards are in place. Does Marinediesel comply?

Like most manufacturers, Marinediesel uses J1939 in the programming on our ECU. J1939 is an incredibly flexible protocol, and there are differences between J1939 for off road and on road use. However, most engine monitoring systems should be able to communicate with our engines, not only with fault codes, but in monitoring performance. Additionally, aftermarket vessel systems that require engine data (such as fuel management systems) should be compatible with Marinediesel engines.

Cylinder head gasket damage: Is it the cause or a symptom?

The failure of the cylinder head gasket is often blamed for causing severe engine damage in marine engines. However, if gasket failure a cause of damage or is it merely an indication of other, more serious problems?

Gaskets are designed to seal. They either keep various matter inside of something or keep it out, whether gas, solid, or liquid. In the case of cylinder heads, gaskets deal with three different components, all related to combustion:

  • Oil
  • Water
  • Gas

If a gasket is properly installed, it should function as designed for a very long time. What are the indicators of gasket failure?

Namely, that the gasket is no longer sealing. The cylinder head gasket not only seals the cylinder from external factors, such as preventing water from getting inside the cylinder, but from between different cylinders on an engine (such as gas from one cylinder leaking into an adjacent cylinder. Obviously, such leakage interferes with the combustion process, and engine damage is the inevitable result.

So, what tells the operator that a gasket may be damaged?

  • Poor cold starting
  • Loss of power
  • All cylinders not firing
  • Different colored smoke
  • High water temperatures

All of these indicators mean that the cylinder head gasket may be damaged. So, you disassemble the engine and replace the gasket. The problem with this is that the gasket may not have been the cause of the failure, but rather a symptom of a different problem. Gasket failure can be caused by a number of different factors, including:

  • Improper torque on the cylinder head bolts
  • Rapid acceleration of the engine after cold start
  • Roughness on the cylinder wall
  • Uneven cylinder top
  • Loose cylinder liner
  • Compression incorrectly set in the ECU
  • Defective thermostat
  • Cooling system blockage or leak
  • Pump failure
  • Exhaust system back pressure caused by either leaks or blockages

How do you know that the gasket itself caused the failure?

  • Discoloration of the gasket (The area of discoloration usually shows the location of the leak, due to heat, whether caused by the gasket or something else.)
  • Excessive flexibility
  • Corrosion along the edges or eyeholes of the gasket
  • Rough surfaces on either the gasket or engine block

This last point is critical. Modern gaskets for marine use are designed of materials that are engineered to be resistant to corrosion and degradation. In most cases, if it is the gasket itself that has failed, rather than another part of the engine, it is usually the result of improper installation of the gasket. In particular, improper tightening of bolts and installation on dirty surfaces causes these issues. Why?

Simple. The gasket must seat properly and seal. Tightening bolts too tightly warps the gasket, preventing the seal. Dirt or liquid under the gasket prevents a proper seal. Since combustion produces heat, the problems are magnified as the heat becomes excessive, further speeding up failure of the gasket.

So, what can be done?

  1. Refer to your manual. Marinediesel always lists the torque for bolt tightening in the manual.
  2. Use only OEM Genuine Spare Parts. The gaskets we use are designed for the engine and made of materials intended to withstand their designed use.
  3. Realize that gasket failure may be a symptom, rather than a cause. If something is causing gasket failure and that cause is not corrected, the failures will continue.





When does outboard power become ridiculous?

Outboard engines have their place and uses. However, a trend over the last few years has been to simply add more outboards to a hull in order to give it more power. No longer are there simply triple or quad outboard installations, but sometimes even five, six or more.

At what point does simply adding more outboards become pointless?

When the costs outweigh the benefits.

The vessel pictured is a pretty well-known photograph of a drug-runner caught in the English Channel (a “scandal” in the UK marine industry at the time). It essentially is engine and fuel tank. Now, most people are not buying boats for smuggling, but are intending to use the vessel over an extended period of time. What does adding extra engines actually do as far as performance?


  1. Added weight (not just the engine, but all equipment, such as mounts and the weight of extra fuel).
  2. Added drag.
  3. Reduced maneuverability.
  4. Reduced safety (often, the hull was not designed for such applications)
  5. Huge increase in fuel costs.
  6. Reduced running time and range (unless larger fuel tanks were designed or installed)
  7. Greatly increased maintenance expense
  8. Difficulty in ventilating the props.



  1. Greater power.
  2. Greater acceleration.


Note that the negatives are pretty big, compared to the positives and their associated costs. Of course, these negatives can be minimized by using diesel inboard engines.

Should a vessel be equipped with two 250 hp outboards, or a single VGT 500? What about instead of three 300 hp Mercury Verados, two VGT 450s?

Unless the vessel has absolutely no room for an inboard, the inboard option will win every time.

  1. Weight: Two Mercury Verados weigh 586 kg. A single VGT 500 weighs 515 kg. Even with gearbox and drive, the weight differential is only around 100 kg.
  2. Drag: Fewer engines mean less drag. All of the time.
  3. Maneuverability: Even numbers are more maneuverable, due to less torsional pull. However, the reduced drag and greater number of propulsion options mean that a single inboard will be as good as or more maneuverable than multiple outboards.
  4. Fuel: No contest. A single diesel VGT will save enough money to pay for the differential in price very, very quickly.
  5. Range: Likewise, the range can be longer, with smaller fuel tanks.
  6. Maintenance: Though an inboard diesel, depending on engine compartment and configuration, is less accessible, it will have a far higher life cycle and require less maintenance and access.
  7. Acceleration: Multiple outboards can accellerate very quickly. But guess what. A Marinediesel VGT engine, designed for high speed craft, will accelerate faster.
  8. Service life: A VGT engine will last as much as five times longer than even the highest quality outboards.

In the Tropics? Keep your engine running cool

Tropical conditions are challenging to marine engines. Engines require both air and water for cooling, both of which act efficiently in removing heat. However, in the tropics, the warmer air and water temperatures reduce the efficiency of your cooling system. So, what can be done?

Marinediesel takes the first step in rating your engines for the operating climate. This is one of the benefits of using Marinediesel’s VGT Series: our NIRA ECU allows such changes in rating, avoiding the sometimes large loss in horsepower often shown by the engines made by our competitors.

What can you do?

  1. Check the raw water intake and make certain that the seacock is opening / closing properly.
  2. Make certain coolant levels are topped up.
  3. Check your strainers for debris or blockages.
  4. Check your exhaust system to make certain there are no blockages.
  5. Make certain the air filter is clean and there are no blockages.
  6. Keep your fuel tank topped up. Warm weather increases condensation in the tank and thus, the likelihood of introducing water in the fuel.
  7. Make certain that the louvers venting into the engine compartment are not blocked and that there is adequate ventilation. If not, a blower may be required in extreme conditions.

All of this sounds like basic maintenance procedures, and much of it is detailed in your engine manual. It just pays in the long run to pay extra attention to these items if the vessel will be operated in harsh conditions.

“If it sounds too good to be true, it probably is…”

Recently, it was brought to our attention by a customer that he “found a VGT engine for sale in the USA, at about half the price we were charging”. This got our attention for a number of reasons. We are long term licensees for General Motors, and all of the licensees pretty much know each other, and what they are doing. So, what gives?

The answer is re-manufactured, or “Reman”, engines.

Re-manufactured engines are a step up from rebuilt engines. When engines are rebuilt during their overhaul, the parts used may be the same, replaced, or repaired. A re-manufactured engine, on the other hand, is an engine that is stripped down to its’ bare components, and built up to a “like new” condition, with parts and components replaced, modified, or even upgraded. In general, there is nothing wrong with purchasing a re-manufactured engine. Many reman companies perform excellent work, and it is possible to buy a reman engine that will give you many years of service, usually at a much cheaper cost.


Re-manufactured is not the same thing as new…

On OEM new engines:

  • All parts and components on the engine are new. They have never been used.
  • Most manufacturers (including Marinediesel) have extensive testing and quality control procedures in place.
  • When buying a new engine, the full warranty is in effect.
  • Engines are ensured to meet quality and emissions regulations.
  • Engine manufacturers typically have robust dealer networks for spares and service.
  • Some components, like ECUs, are difficult to replicate, necessitating replacement with a different unit.
  • Though manufacturers may use the same engine blocks, many parts are customized by each manufacturer, some of which, like pistons or cylinder heads, are not easily modified or duplicated.

If a re-manufactured engines is sold as a new engine, then the practice is deceptive. Most reman companies are not doing the actual research and development work. Most re-manufactured engines have greatly reduced or highly limited warranties. Components on the engine could come from a variety of different sources that may, or may not, have been properly tested. Most vessels cannot be classed with re-manufactured engines, because the engines themselves cannot be classed.

So, the competing engine at half price? It was a re-manufactured engine. Though the engine may very well perform as the buyer expects, it also could cause problems in terms of life cycle, and depending on location, service (In this case, the buyer will be in for a rude awakening when the engine needs service). Additionally, though the customer claimed it was a “VGT” engine, the engine most certainly was very different in terms of performance. Though it may resemble the Marinediesel VGT, and share the vsame engine block, the engine itself was a completely different engine. So, yes, the engine was cheaper. But it was, certainly, not the same.

What is important to consider is the old cliche: “If it sounds too good to be true, it probably is…”