What is the difference of functions between marine engine and truck engine?

Question

My boat is under construction, capacity of 60 to 80 passengers, so that is why I’m looking now a suitable engine for this boat.

Answer 1

Marine is for the marine environment & a truck engine is not>But converted some truck engines are use for marine>

Answer 2

James is right- I just wanted to add that the starter and the alt are both spark producers. So they must be sealed or properly vented with fire block(Fine wire mesh which absorbs and heat(read explosion) before it can escape the confines of the device.

Answer 3

Ask your marine engineer for his suggestions. If the vessel is under construction, what do your plans allow?  Most marine engines are diesel piston, and are designed for the environment.  Insurance for a vessel and CG certification for passenger use will mandate marine rated engines. Ask your engineer/ architect. That is what you are paying them for.  

Answer 4

A far more encompassing and basic answer is in 2 parts:

1.The engine must be entirely contained i.e any thing that can go into or out of must be controlled.

2.The engine must function whilst rotated through all planes.

Stops stuff poluting the hull ( liquids or gases) and means the engine will run in rough weather or capsize situation.

Answer 5

also they maybe turning counter clockwise depending on what type of engine and or out-drive  go diesel

Answer 6

Marine grade engines normally use stainless steel head gaskets, Brass freeze plugs, more aggressive cams for better high revolution power, sealed electronics for protection from environment and to prevent fires, stainless component water pumps, some contain locations for sacrificial anodes, ignition systems designed for different target RPM range, if it is a carb model the carb is required to drain any overflowing fuel into the engine unlike automobile designs.  Aside from these differences truck and marine engines are essentially the same.  Blocks and heads are interchangeable between the two designs.  It is possible to convert a truck engine into a marine engine but certain changes are a must in order to insure longevity.  And no matter what always use marine grade ignition components, you don't want sparks.