Questions About Marine Diesel Engines

Boat engines face unique challenges as they must be able to provide power and withstand corrosion. Consequently, the design of a marine diesel engine is markedly different than the design of the engine that powers your automobile. You?ll find new and used marine diesel engines in an assortment of different makes when you shop on eBay.

How are boat engines different from car engines?

Marine diesel engines differ from automobile engines in two key respects. Firstly, they typically experience much higher loads, so they have to work a lot harder when they?re providing propulsion. Secondly, most older boats use a water-circulating pump rather than a contained cooling system. These two facts have direct implications on the types of engines used in boats. There are two types of marine diesel engines: four-stroke and two-stroke.

  • Two-stroke process: Air is inserted into a cylinder that pushes out exhaust. When the piston moves to the top of the cylinder, fuel is added, and when the fuel combusts, it pushes the piston down again.
  • Four-stroke process: During the intake stroke, fuel is injected and the piston moves down. As the piston moves up again, it compresses the fuel/air mixture. At the top of the compression stroke, the fuel/air mixture ignites; the explosion drives the piston down and the exhaust fumes are dispelled.
What are the advantages of two-stroke marine diesel motors?

There are many reasons to choose two-stroke marine diesel motors:

  • Simple construction: Two-stroke motors don?t include valves, so they?re much easier to maintain and repair.
  • Compact size: Two-stroke motors are smaller than four-stroke motors, so they can be used as outboard motors. This gives you more room on the vessel itself.
  • Power: Two-stroke motors are generally more powerful for their size since they offer twice as many strokes in the course of a single revolution.
What are the advantages of four-stroke marine diesel motors?

Affordable four-stroke marine diesel motors on eBay offer the following benefits:

  • Fuel efficiency: Four-stroke motors use fuel more efficiently than two-stroke motors, which means you?ll get more miles per gallon.
  • Emissions: Four-stroke motors typically put forth fewer emissions than two-stroke motors.
  • Computerized management systems: Most four-stroke boat motors on the market today feature computerized management systems, which offers trouble-free performance with minimal stress.
What kind of maintenance dose a marine diesel engine need?

Two-stroke motors require oil injections while four-stroke motors require oil changes. You?ll need to fill the two-stroke motor?s oil injection reservoir regularly with whatever kind of oil the manufacturer recommends. Your four-stroke motor will need to have its oil and oil filters changed at routine intervals, and you may also need to make valve adjustments periodically to keep it in optimal running shape.