Join Date: Aug 2002
Location: Ogden, UT
Thanked 4 Times in 4 Posts
Rep Power: 15
Re: water leaking in oil - Universal Diesel 5411
The 5411 is a very similar block to mine, the 5416.
These engines have a history of overheating causing the cylinder head to crack, allowing water to mix with the oil. I think the common location for the crack is right in the middle of the head, between the two combustion chambers. Since the 5411 is raw water cooled, the passageways are prone to clogging up due to salt deposits, making this engine even more prone to overheating and the head cracking problem.
I am not sure if the 5411 has an externally mounted raw water pump or not, but if it does, it is driven off the injector pump camshaft. If the pump seals fail, water will enter the crankcase by getting past these seals.
1980 Bristol 29.9