Re: water in pistons and oil pan
If it were mine I would start with a vacuum guage test. If you are skilled with how to read one and recognize what it telling you it can be a very good indication where the problem area might be. I'd then do a compression test on all the cylinders. If you don't have good diagnostic skills it's going to be a little tough. You may wind up having to seek out a professional mechanic. Water in those places just don't sound good at all. Could be a lot of differant things. Intake manifold gasket, head gasket, etc. Keep us posted. And then againn it could be none of them.
