Kohler M-20 exhaust pipe smoking
 

Hi guys. I have a Kohler Magnum M20 on a Cub 2082. I got this about 4 months ago. I broke down and cleaned the carburetor and reassembled to Kohlers specs. The motor starts up and runs great. After about 3 minutes or so i notice that the exhaust pipes that run from the heads to the muffler behin to smoke. It is not heavy but it is enough to concern me. I will try to post a video.

Forgot to mention that the noise in the background is my wife using the leaf blower and not the engine. The engine runs very well and strong.

Probably got something on them while you were working on it. Fire it up and let it run. Whatever it is will burn off. Just make sure you don't have something against them that isn't supposed to be.


By the way, those manifolds should be covered by the top engine shroud. Shouldn't be able to see them. You missing a shroud?

Kohler motor exhaust pipe smoking
 

http://youtu.be/trW5FalDLVk


Thanks. I dont think anything has spilled on them however, i will run it for a few minutes this evening and see if the smoking stops. Thanks for letting me know about the shroud, unfortuneatly it came without one. I may try and fab one up over the weekend.

If by chance you have an extra shroud Please message me.

Thanks

The rear seal may be out and the fan blowing oil forward. You are missing several shrouds. I suggest pulling the motor all the way out and cleaning it up good. Power wash it with de-greaser. You need to remove all the shrouds before washing it. Most people never clean their tractor engines. It's a good thing to do every few years. I blow the engines out of mine regularly to keep things from getting built up. May have a bunch of junk on the back of your jugs, therefore air cant get forward to cool things off. The smoke only indicates that something is getting on the manifold.

Ok, i did not mention it, but i did pull the motor and had all the shrouds off and scrubbed the entire motor down and replaced both shaft seals and also pulled the jugs and replaced those seals and did a valve job a month or two ago. The motor is very clean. I am wondering if there isnt some sort of blockage in the muffler. I am going to swap mufflers and see if there is a different outcome today.

No, you didn't mention that.

The way the muffler is made, it can't really have a blockage in it.

If you have replaced the rear seal, and know you don't have any leaks, then I'd say that you just have residual oil on the manifold, or even a jug, and it's just burning off. Let it run, it will quit smoking after while.

Gotcha. I will run it this evening and report back. Only leak i have found is at the oil line adapter to the motor. I have replaced that gasket three times and still have just a little seepage there. I know that is a common problem with these kohlers. Uggg so i will be making a gasket tonight and use permatex to see if i can get it to stop seaping oil. I wish they would have designed that adapter a little different. Also do you have any additional tins to cover the exhaust manifold? If not i will be looking online in my local area for a parts cub. Parts tractor maybe the way to go since i could use a better plastic hood.

I've not ever seen that gasket be an issue. Better buy the correct gasket. Make sure to get the correct one, there are two different styles.

No, I don't have any extra tins to sell. Sorry man. Put up a wanted ad on this site though. Bet someone here has some.