getting water in my engine oil on my yanmar...is it head gasket or some other defect///
First of all - Welcome to SailNet!
Second - SailNet is a great place for sharing your experience, and reading other people's (some experts, some not) opinions, suggestions, and assistance.
(I've said this before; "free help is frequently worth less than you pay for it."
Third - you'll get better opinions and suggestions with more detail. Right now I know that you have a Yanmar, and there is water in what you believe to be
the lubrication system.
Questions; What kind of boat is this engine mounted in? How do you know that there is water in the system? (water on the dipstick?, you see water when you open the oil fill - and not the FWC
- cap? you dropped the oil pan and see mayo?
) How long have you owned the boat, and how long has this Yanmar been installed in it? Is there any obvious reason that the water is getting somewhere that it shouldn't? (ie. is the bilge full of water?) What does the liquid in the FWC look like?
It is POSSIBLE that you are merely experiencing H2O condensation in the engine block, and it will burn off when the engine is brought up to temp. It is POSSIBLE that your cylinder head gasket has a break in it that is allowing the FWC system and lubrication system to bleed together. It is POSSIBLE that the motor is kept behind your garage, and covered with a tarp?...
I could go on, but you need to give us something more to work with...