i rebuild my 472 and drop the engine back in put in oil and was putting in coolant and water came out the oil pan :bomb:maybe its the timing cover info out there :banghead:

Intake manifold? I wonder if some of the head bolts require sealant? Something is seriously wrong there.

Not to insult you, but did you possibly leave a head bolt out? If so, it would have a lot of water flow through that opening, and run down through the oil drain openings in the head. What CadillacAl said made me think of this, and we all make mistakes. The timing cover could maybe be the problem, like you mentioned. That plate usually has rust pits in it, and it's hard to seal. Over at www.cad500parts.com, they have a new plate made of stainless steel for folks that can't use the old one because of pitted surfaces.