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Kohler engine starts and runs fine for a minute or two, then it acts like one cylinder fires intermittently at first then runs on only one cylinder. If I shut it off have to wait for it to cool down before it will restart.

Try this. When cold remove one spark plug wire and trying starting, if it starts replace and repeat on the other side. If it will not start when open side is removed, the other side is bad. If both sides start repeat when engine is hot. Causes for one side going bad are many. Bad plug or coil, valves out of adjustment, bad intake manifold or carb problem, and finally bad head gasket. You’ll need to do some more troubleshooting to find the problem, keep us posted.

Rivets said:

Try this. When cold remove one spark plug wire and trying starting, if it starts replace and repeat on the other side. If it will not start when open side is removed, the other side is bad. If both sides start repeat when engine is hot. Causes for one side going bad are many. Bad plug or coil, valves out of adjustment, bad intake manifold or carb problem, and finally bad head gasket. You’ll need to do some more troubleshooting to find the problem, keep us posted.

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Thanks, it will not start at all when hot.

You now need to figure out if it is a spark or fuel problem. When hot are both plugs firing? Have you tried starting when hot by spraying some carb cleaner directly into the carb air horn? I’m thinking you may have a bad coil. When you post back, include all engine numbers.

Rivets said:

You now need to figure out if it is a spark or fuel problem. When hot are both plugs firing? Have you tried starting when hot by spraying some carb cleaner directly into the carb air horn? I’m thinking you may have a bad coil. When you post back, include all engine numbers.

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I listed it as a 20hp Kohler engine, it is a 22hp, 7000 Elite series, Engine model number KT725-3023, serial # 4406506504. Since I posted this I had been unable to get it to start until today. I removed the air filter and put gas in the carb intake and had to turned the starter for a few seconds before it would start. What I have discovered is it runs good until it warms up, as long as the throttle is kept below about half and the deck isn't engaged. If you throttle it up the engine bogs down, it actually sounds like one would sound if you had it throttled up about 80 to 90% and turned the key switch off. It wasn't doing this before. It will start hot as long as throttle is about 1/4 open. The spark appears to be weak on both cylinders.

What you have don is confirmed that the coils are working ( might be slightly out of time ) , the valves are working and the idle / primary side of the carb is working.
Your problem is with the main running jet / circuit.
The jets clog up because they are too small and they also fall out
If it is the former then the exhaust note should sound higher and sharper and the engine might speed up slightly before it dies
If the latter then the exhaust note should get deeper, slow down & sound a little hollow just before it dies and perhaps just a little black smoke .

bertsmobile1 said:

What you have don is confirmed that the coils are working ( might be slightly out of time ) , the valves are working and the idle / primary side of the carb is working.
Your problem is with the main running jet / circuit.
The jets clog up because they are too small and they also fall out
If it is the former then the exhaust note should sound higher and sharper and the engine might speed up slightly before it dies
If the latter then the exhaust note should get deeper, slow down & sound a little hollow just before it dies and perhaps just a little black smoke .

Click to expand...

After disassembling and reassembling the carb, I decided to try replacing the fuel pump with one off of an older model John Deere. Now I feel a little foolish due to the fact the pump was the problem. Should have checked it first.
Thank you very much for your help!