Kohler 15hp backfire

[Lawn Man 5]

Every time i shut my motor off it backfires, (it probely has about 100 hours on it). Is this normal. If i let it idle down it won't. Will it hurt the motor if i let it backfire.

Thanks

[khouse]

If your muffler is thin or rusty it can blow a hole in it. You can fix your problem by shutting the engine down at 3/4 to full throttle. Try it and let me know. It won't hurn anything.

[Lawn Man 5]

That is when it backfires, if i let it idle for about a minute it won't backfire. When I go from full throtle or 3/4 and shut it off it really bangs. But I like to just turn it off.

[khouse]

Each engine - even the same engines seen to have their own way of starting and running. If yours wants to be at idle for a minute before it shuts down then you may have to keep doing that. You can also check to see if your engine is running hot by chaff build up in the engine.

[Bo Jack]

I have the 14 Hp with 380 hrs and it does exactly the same (backfire). Use the same procedure as you for shut down.
Guess its the nature of the beast

[catsnglf]

I was told by a dealer that the Kohler will backfire unless you let it idle for a minute or two before shutting down. They didn't explain why, just that they do if you turn it off without idling. My 16 HP did it too, but now that I let it idle it doesn't.:rolleyes:

[Robert Doubrava]

I recently emailed B&S asking a question about my riders engine backfiring when shutting down, and he said to let the engine idle before shutting it down, and you should have no more problems.:)

[scottb]

Its a good practice to let most any engine idle before you shut off.

[Jman]

If your engine has a fuel shut off solenoid on the carb, shut it off at 3/4 to full throttle. If no solenoid you will need to let it idle for a minute or two to cool the exhaust system down. To let them run at wide open with NO load will actually cool the engine down but not the exhaust system. Remember these are air cooled engines. When we let them idle the fan doesn't blow as much air past the engine and doesn't cool it properly. The backfire is caused by unburned fuel hitting a hot spot in the muffler and igniting it.

[Jman]

If your engine has a fuel shut off solenoid on the carb, shut it off at 3/4 to full throttle. If no solenoid you will need to let it idle for a minute or two to cool the exhaust system down. To let them run at wide open with NO load will actually cool the engine down but not the exhaust system. Remember these are air cooled engines. When we let them idle the fan doesn't blow as much air past the engine and doesn't cool it properly. The backfire is caused by unburned fuel hitting a hot spot in the muffler and igniting it.

[Scotlawncare]

PLEASE DO NOT SHUT OFF YOU ENGINE RIGHT AFTER IT HAS BEEN RUNNING AT FULL THROTTLE OR 3/4. Always let it idle down for at least for a few seconds before you shut it down. You are killing the spark on a high reving moter that is still getting alot of fuel. Possible high fuel load and a spark will blow something.

Please if you value your equipment let it idle a min before you shut it off. even your 2 cycle motors.

Scot

[Jman]

If the carb is equipped with a fuel shut off solenoid in the base of the carb it will get NO fuel into the engine when it is shut off at full throttle. That shuts fuel off to the main jet of the carb. It does not shut off the fuel flow from the tank to the carb, just the high speed jet. It does not shut off fuel to the idle jet of the carb. There again if it is shut off at idle and equipped with the solenoid, you will still pull fuel through the idle jet into the engine and could cause the after fire in the muffler or give you a dieseling effect. This procedure, if equipped with a solenoid is totally backwards from what has been taught for years and years. Has anybody read the owners manual on their new Kohlers? There is a paragraph on stopping the engines, one on with the solenoid and one without the solenoid.