Did you remove the head? If no, then it could be the o-ring that you damaged when putting back the cover and might have blocked the weep hole?
Do you smell exhaust from the radiator? Bubbles in radiator? That's a quick way to check for leaks in the head.
What seals did you change? Cracked cylinder sleeve from overheating if you accidentally ran the engine too long and hard with the water leakage before?
I'd guess it's just condensed air/water in your crankcase if you didn't mess up during assembly.