Marine Engines Key Terms

These marine engine vocabulary terms will help you get into the flow

By Cathy Salustri

Diesel marine engines work in much the same way as other diesel engines. Diesel marine engines such as Volvo Penta, Cummins and Perkins differ from brand to brand but the principle behind the engine remains the same. Learning some basic terminology about these engines and the systems they employ, such as lubricating, cooling, electrical and fuel systems, will help you understand how a marine engine works. Use the diagrams and the articles to fully develop your knowledge of these basic terms relating to diesel marine engines.

Diesel engine

Marine diesel engines, like any other diesel engines, are internal combustion engines that use diesel fuel instead of gasoline. Diesel engines use heat generated by compression (rather than spark plugs) to burn fuel.
Try: The United States Department of Energy explains the principles behind diesel engines and how they work.

Camshaft

The camshaft in a diesel marine engine includes the camshaft, pushrods, rocker arms and valve systems, as well as other components.
Try: Engineers Edge has a labeled diagram and accompanying article that describes a camshaft.

Lubrication system

The oil pump, piston cooling, relief valve, oil cooling valve and piston cooling valve, oil filter, oil cooler and crankcase ventilation all comprise parts of the engine's lubrication system.
Try: The Maritime Park Association has an in-depth article that discusses the parts of a diesel marine engine's lubrication system.

Fuel system

A marine engine's fuel system has an injection pump, feed pump, centrifugal governor, injectors, relief valve, air filter and fuel filters.
Try: Don Casey explains how to maintain a fuel system on a diesel marine engine and, in doing so, describes each part of the fuel system and what it does.

Cooling system

The two main parts of the cooling system are coolant and a thermostat. Marine engines also use raw seawater to cool the engine.
Try: Diesel Power has a four-page article on a diesel engine cooling system. And, Long Island Marine Surveyor explains water cooling systems (both fresh and raw sea water) and how they work.

Electrical system

The electrical system includes fuses and a stop solenoid. Some industrial marine diesel engines do not have a stop solenoid. A solenoid has an iron core and becomes magnetized when an electrical current goes through it.
Try: Marine Parts Express explains what a solenoid does in addition to how fuses work on a marine diesel engine.