Thanks Bax I know the glow plug is tight Will check head bolts. As I pull the engine toward, TDC I can hear air going past the ring while I listen in the carb and from TDC on the down stroke , I hear air leakage on the down stroke until the piston gets to the exhaust port. Will put another gallon thru it and if no change will send it back. It is for a spring project, plane is built. Thanks. Bob