AboutJohn Expertise I specialize in two cycle questions and repair, specifically
chainsaws. But have worked on Outdoor Power Equipment for 18 years.
So lawn mower/small engines are also what I work on everyday. Being
in KY, snowblowers are very rare, so their drive systems I am not familiar with. Electrical work on Generators is something I do
not get into either, as I have no training in that area.
Also, I have little experience with boat motors, mini bikes, 4 wheelers, motorcycles, etc.
Experience I have worked in the Outdoor Equipment Industry since 1990,
and have been active giving online help to do-it-yourself types
since 2000, and also am skilled in parts lookup help as well. When
working at larger dealerships, I have always filled the "Two Cycle
Man" position, as it is an area that can be tricky to diagnose and repair.
Publications Online forums
Education/Credentials Briggs, Kohler, Tecumseh, Stihl schools and updates
I have a z-42 Cub cadet model 53AC305G100 with a Kohler 15hp pro series, model number CV15S spec # 41535.
What happens is that the mower will run fine for 20 minutes then it dies. It worked fine the first of the year but the last two times I have mowed it started doing this. I have checked, it is not a fuel problem. When I check the spark plug it has no spark. I have tried changing the plug and get the same result. If I let the mower set for an hour or so it starts right up and runs fine for another 15-20 minutes then dies again. There seems to be a direct relation to how long I let it set and how long it runs. The longer I let it set, the longer it runs.
It seems to be heat related. I am wondering if this could be a coil problem? I have had someone say it could also be an exhaust valve problem? How do I determine which it is and how involved is fixing an exhaust valve?
Thank You for your time,
Tony
Answer Looking at the engine blowup, you have hydraulic lifters, and if
there was a valve problem, it likely wouldn't run at all, unless it is a loose seat, but after a couple of times, wouldn't start again.
Coil could be breaking down, but I see your system has an oil switch
which could be a big possibility.
If it is due, change the oil and filter, use 10w30 and make sure the oil level is at or slightly above the full mark, and see if the problem gets better.
