i have a craftsman rider, was grandads, now mine, has a kohler 26hp on it, model CV25S, spec 69526, serial 2735104591, i think its a early 90s model, it will start and idle, however it pops through exhaust, if i try to throttle up, it does not, just pops worse, sounds almost like timing is off or its missfiring real bad, it almost stops poping if i pull choke just a hair, so far i have put new plugs, checked push rods and rockers, i checked for chewed wires, compression is great, i pulled engine, pulled oil pan, thought mabye compression release was stuck, nope, it dont have one, or atleast on the cam, camshaft is nice looking, mower only has 260 hours on it, i changed voltage regulator, and oil, both cylinders are sparking, just dont know if its right, i am so lost, there is a little black box on passenger side of motor, thought it might be a cdi unit but i dont see anything anywhere that says anything about a cdi, i am a diesel mechanic by trade, just cant figure this one out, please help, thanks in advance!
