Cub cadet tractor with Kohler ks540 engine running rough.

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RaginMad55

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• Sep 22, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #1

Hi I have a Cub cadet xt1 lt 42” with a Kohler ks540 engine. When I cleaned the outer engine with carb cleaner I sprayed a little at the air filter intake and now it doesn’t run right. Keeps running really rough even after it should have cleared out the carb cleaner. Did I really screw it up or is there something else I need to be checking out?

 

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slomo

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• Sep 23, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #2

RaginMad55 said:

When I cleaned the outer engine with carb cleaner

Click to expand...

Don't know what to say about this???

RaginMad55 said:

Keeps running really rough even after it should have cleared out the carb cleaner.

Click to expand...

Is the choke stuck closed? Choke even work properly?

 

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Auto Doc's

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• Sep 23, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #3

Was it "carb cleaner" or engine degreaser? This has me curious.

Maybe a bunch of debris is inside the main engine electrical connector? Carburetor choke is stuck?

 

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RaginMad55

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• Oct 1, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #4

Sorry reply took so long and No choke is not sticking. The same thing is happening to my other tractor. Running erratic and popping while running ahhh. Went through fuel system and no issues. Wondering if I got some bad gas from station or if it has water in the gas since both tractors are having the same problem.

 

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Auto Doc's

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• Oct 1, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #5

Try pouring a half bottle of Isopropyl rubbing alcohol in each fuel tank and then drive it around constantly changing speed and direction to mix it really well with the existing fuel in the tank. I have corrected several cases of questionable fuel quality issues that way.

Ethanol and Isopropyl are not the same so don't get it confused. Look them up.

 

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slomo

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• Oct 2, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #6

Pull the fuel line off AT the carb inlet. Drain into a glass jar. Look for water in the bottom. Turn the key on if you have a fuel pump on the engine.

Remove the carb bowl and dump out the contents.

Any evidence of water, drain the entire system.

 

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RaginMad55

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• Oct 3, 2025 / Cub cadet tractor with Kohler ks540 engine running rough.

• #7

I did remove the fuel line and dumped some in a glass jar and couldn’t tell if it had water as the jar was beveled on the bottom and checked the fuel filter which seemed ok as it was flowing gas through it. But I will try again. And will try the isopropyl alcohol too. Wish me luck and thank you.