Diagnosing internal engine damage (water in oil)

[UTboater]

Hi everyone,
Is there a tell-tell sign that an engine block or head is cracked from freeze damage? Short of taking it apart? There are no visible signs of damage outside the block and the engine runs okay.

The boat had set for a long time and I thought this was probably the cause of water in the oil. So I drained the pan extra good and put back new oil and filter. After running the boat a while, I noticed that the oil looks much much better but there are still signs of a small amount of water. My plans were to just keep changing it until it is totally clear.

After the boat has run a while, the oil level remains the same so I'm guessing the engine is not taking on "new water" like it may with a cracked block or head.

Could a crack allow only trace amounts of water in or would it be more noticeable?

I've had conflicting diagnosis from two different marine mechanics so I would appreciate any thoughts so I could make a more educated conclusion.

Thanks so much

 

[zbnutcase]

Re: Diagnosing internal engine damage (water in oil)

It would help if we knew what engine we are dealing with!

 

[UTboater]

Re: Diagnosing internal engine damage (water in oil)

Yeah sorry, first post of course. Darn noobs :redface:

It is a 1994 Marada. 3.0 GL Volvo 4-cylinder, Penta drive. Seems to be all original equipment.

Thanks

 

[bruceb58]

Re: Diagnosing internal engine damage (water in oil)

You can pressurize the cooling system.

If there was a small amount of water in the engine for reasons other than a cracked block, it may take a few oil changes to get all traces of the water out.

If you have bad manifolds and risers, a small amount of water can collect on the pistons after the engine turns off. Some of this water could leak past the rings and into the crankcase so make sure your manifolds/risers are in good shape.