Thread: Marine Diesel Engines

In my time at sea we converted several engines to marine use, it usually involved a different manifold for cooling as they don't usually run a fan and radiator , and they were converted to 24v. a different flywheel if used for gen set application.


Not sure about small engines like you mention but cant see it being much different in smaller boats.


Cheers Ean

Marine conversions of road-going engines usually involve at a minimum, fitting a watercooled manifold and a marine gearbox, but many engines will require an oil cooler as well. Since it is not a good idea to run sea water in the cooling system of an engine not designed for it, it is usual to run a separate heat exchanger, which means an additional sea water pump is required.

Many conversions have been derated compared to their road going version (because there is no airflow), and this usually means remapping the fuel system as a minimum, but it may have a completely different fuel system, especially if it is a fairly modern engine, as emissions regulations do not usually apply to marine diesels, and it may be able to be simplified.

John

Originally Posted by Lionelgee

Hello ALl,

A couple of times I have come across engines that have been converted to marine use. For example, a while ago there were two engines: a Nissan SD33 and a Isuzu 4BB1 that had been taken out of different boats. The sellers mentioned that the engines had been converted to marine or maritime use.

What things would have been done to these motors when compared to the same engines that powered things like the Nissan MQ Diesel Patrol or the Isuzu ELF trucks?

Can these marine engines be converted back to being used in a car?

Kind Regards
Lionel

In my yacht I had a BMC Commander then a Perkins 4-108.
Both basically light truck engines.

One thing to watch for is corrosion of the water galleries as they may have had salt water run through them if the PO was too tight to go for a fresh water heat exchanger

Keith

JDNSW has it well covered. My yacht has a universal diesel which is a marinsed kubota tractor engine. It has a water cooled manifold, raw water pump and a bolt on heat exchanger for seawater/cooling. I don't know what the engine looks like in the tractor but the changes appear to be all simple bolt on additions.