Radiator pressure tester borrowed from an auto parts house is the easiest way. Start up white smoke is probably water. If there's water in the oil it will look like chocolate Yoohoo, creamy tan instead of oilish. The water will be on the bottom so a short oil drain (let just a dollop out and replace the plug) will show that. If you drain it into a clear container you can see small water "bubbles" on the bottom.

There is a water jacket in the intake manifold, too, and is a possible source of water in the engine.

Last edited by fasteddy; 01/26/13 01:18 AM.
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