water leak

Is it a lot or a little? If a lot, I would stop running it, and just get ready to tear it down. If a little, then I would do a pressure test on the colling system to see if there is high pressure. If so, then I would suspect a head gasket. If not, then a crack in head or block.

So what machining was done to the motor when it was stroked? And re you running anti-freeze?