[James Rogers]

40 Deluxe is on the right track. You are probably having a problem with expansion of the pistons tho, I have never had one seize when shut down. I have had pistons that seized or almost did while running. This most often or always happened when I used older split skirt pistons. I always hone to .004-5 for clearance using pistons available from Snyder's. This is to coincide with a ring end gap of .004 per inch of piston diameter or, .014-16. As for the .002 bearing clearance, I always set mine at .0015 -.002 so, .002 is at the top of the range and close to too loose. I have never had a problem with these practices and have many motors running happily.