im having trouble wth a 25hp kohler command engine. one of the cylinders doesnt fire. i checked spark its perfect. not sure about the gas but on the plug it seems to have enough. i did compression check it and the bad cylinder had 110psi and the good had 120 but i but a liitle oil in the spark plug hole on the bad cylinder and it rose to 130psi so i think its the rings but not sure?model # CH15S SPEC # 68503 Family # SKH725U1G2RA any suggestion welcome!