The Stovebolt Site Forums The Shop Area Engine Shop indications of a gasket leak?

I recently was able to get my rebuilt motor started. I was told by my Dad that indications of coolant leaking into the piston chamber is white exhaust. So the other day when I fired it up, I saw what I thought looked like white exhaust for about 15 to 30 seconds and it went away. He also said that I can look into the radiator and if I see bubbles come up, then there is a leak. I don't think that is a good indication, because there is the return hose spitting water in really close to where I'm looking. The bubbles that I see (only when I rev it up) are small enough they almost look like dust. I kind of think it is the return coolant making those bubbles. I did retorque the head and got some movement out of every bolt. Just thought I'd see what everyone else thinks. Everything runs fine. I just get paranoid when something doesn't look like what I expect it to look like. There was that white exhaust one time, and the little bubbles in the radiator when I rev it hard. what other things can I look at to confirm something is wrong?