Perkins 4.107 vs 4.108

[Kokonut]

I have a 4.107 which runs very well, other than a most recent issue I'm experiencing with the transmission (high oil pressure).

That aside, a boat has sunk and is now sitting waiting to be taken away. This boat had a working but neglected 4.108 and the motor has been out of the water for about 3 days now.

Does anyone know (assuming that the parts from the 4.108 are ok), are there any parts that can be used seamlessly on the 4.107, or is it even worth considering taking the entire engine?

[jimbunyard]

Some of them will be, but these two engines have had such a long and eclectic life that knowing which parts will fit which, even within their own respective models, is at best a crap shoot.

There are plenty of parts and service manuals for both widely available on the web. A close perusal of these and comparison of relevant measurements given in the 'spec' sections of these manuals might be a good place to start...

If the engine was running before, and you drain and refill the oil and run it up to full operating temp about three or four times, it will probably have no ill effects from it's dunking.

The engine still has value purely due to the number that are still out there.

The electrical system will probably have to be replace, though if the boat was sunk in fresh water, the starter and alternator might be able to be 'dried out' and reused, though many will see this as a false economy.

[Lepke]

Electrical parts, starters, alternators, radios, etc., recovered from salt water can be flushed with fresh, allowed to dry, and usually return to working order.
I have rebuilt an number of diesels sunk in salt water. If the engine wasn't running, there is almost no damage if recovered quickly and flushed. But with an engine out of the boat, it's an ideal time for a rebuild.
The 4108 is a improved design and might be worth rebuilding and swapping for the 4107 if the boat is a long term possession.