The marine diesel engine debate

The debate between marine diesel versus gasoline engines is a hot topic - literally. Both engines turn chemical energy into mechanical energy using an internal combustion process. The marine industry argues for the pros and cons of each engine type, with neither coming up on top. There is a lot of information surrounding the topic, however it is often misleading.

The key difference between gasoline and diesel engines is that the air comes first in the combustion process. Air is funneled into the combustion chamber from either an air cleaner unit or a turbocharging system.  A compressor squeezes the air to a high pressure. A fine spray of fuel is then injected into the engine via the fuel pumps. The engine control unit determines when, how long, and the pressure of the spray. Due to the compressed air, the fuel ignites without the need of a spark plug. The combustion makes the piston push back out of the cylinder, producing the power that drives the marine craft in which the engine is mounted. When the piston goes back into the cylinder, the exhaust gases are pushed out through an exhaust valve and the process repeats.

Due to the combustion process, it is said that diesel engines are safer than gasoline engines. Diesel fuel vapors are not explosive, whereas gasoline fuel vapors are, hence why there is no smoking at a gas station. While this is a valid characteristic, it isn’t the main factor to consider as it is not often that an engine will burst into blames. The comparison of the levels of carbon monoxide, however, should be assessed.

A common belief about diesel engines is that they can run for hours without requiring much maintenance. While diesel engines may be sturdier and more consistent in their power output, that does not mean that they are not sensitive to certain working conditions. Typically, diesel engines are installed in heavy duty marine craft that run for hours, in which case, the diesel engine is consistent. If you were to choose a diesel-powered motorboat however, chances are the engine is repeatedly turned on and off. Diesel engines can be worn down by the shorter running times, therefore requiring additional maintenance. This is simply a case of assessing the scope of your marine craft’s journeys.

Whether you are interested in a gasoline or diesel engine, you will be spending money filling up the tank. Gas prices are often used to sway a buyer one way or another. It used to be that marine diesel fuel prices were significantly higher than gasoline. This has since changed, with diesel prices levelling out to those of gasoline. A better point of comparison is the fuel efficiency. Generally, diesel engines have a better fuel economy than gasoline powered engines however, if you were to assess all economic factors, diesel engine powered marine craft tend to cost more to purchase. It will cost you more to maintain a diesel engine compared to a gasoline engine. Gasoline powered engines may experience more problems; however, they are routine and easy to get fixed. In comparison, diesel engines may not occur problems so often, but when they do, the cost of repairs is far greater.

At Aviation Purchasing Platform , owned and operated by ASAP Semiconductor, we can help you find Marine engine parts for the marine and defense industries. We’re always available and ready to help you find all the parts and equipment you need, 24/7-365. For a quick and competitive quote, email us at or call us at +1 763-401-8616.


Semiconductor's Certifications and Memberships

Thank You for Visiting Aviation Purchasing Platform.

We Hope You Will Choose Us as Your Parts Distributor and Logistics Solution.

Request for Quote

We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it.