Hello, you can check the spark plug around where it is leaking,see if the color of it is off compared to another plug. Also, check the oil, does it look milky (light brown and a weird consistency)? If the oil id milky, it means the water is getting into the oil. I would suggest pulling the head off, confirm that it is not warped or the head gasket messed up. You would be able to tell where the water is getting by the head gasket as it should show a discoloration or just look different. Also, you could check to see if the head bolts were at the proper torque b4 removing the head. It sounds like maybe one isn.t tight since it fixes itself as it heats up(the metal expanding). I would still pull the head and investigate. You don't want it to get worse and have water go in to the oil system and wind up blowing the motor. Check for previous posts on here as I am sure I read somewhere that original crate motors (the first couple years they came out) had shotty quality control and it was recommended to have it torn down and everything checked. Hope this info helps.

Mark