I have a case tractor 220 engine apart and on the camshaft gear I find two marks on it instead of just a dot that is for timing the camshaft to the crankshaft. One mark is a dot and the other mark is a "C". My question is what is the "C" mark for? The motor is a 10H.P. Kohler K-241A. anybody out there got any ideas. I cannot find the "C" mark in any Kohler manuals I picked up at the Library,