What would cause a Kohler engine to start to miss after 30-45 minutes?

Question

It runs great, then after 30-45 minutes it begins to miss. Could the spark plug break down even though it looks fine and is gapped properly? Maybe Ignition Module? It's a Kohler Command CH14. Thanks.

Answer 1

go ahead and install new spark plug. but sounds like it is the module.

Answer 2

check the ground wire to the key switch, the wire from the ign. module may be burnt or shorting out, also brigs &stratton makes a neat ign tester  part num.  19368 it will work on any b&S, kolher or tecumseh engine. you hook the one end on the spark plug and the other end on the ign. wire, and check the spark while the engine is running, this tool will save you alot of time in trying to find the problem , you also try disconnect the ground wire , to also see if the problem iin the wiring harness , good luck !!! [ note spark gap is at .030 ]

Answer 3

I had this exact problem with a Honda engine once. Turned out to be the sparkplug. Although the most common problem is the ignition module.