Kohler CH20 running rich

[Mr Mower Man]

This Kohler CH20 on a Cub Cadet 3206 garden tractor is running rich. I've been into the carburetor already, and it's clean. Not sure if the float height is adjustable or not, but it's a plastic float, so I didn't think it was adjustable. There is an idle mixture adjusting screw on this one, but the engine still runs rich even when it's screwed all the way in. If I clamp the fuel line shut and wait for the engine to die, it runs good & smooth for about a second before it runs out of gas. The strangest thing to me on this engine is that it seems to run just fine on each cylinder by itself. Only when I run on both cylinders does it blubber. I haven't taken the exhaust loose yet to see if that's my problem. Any thoughts?

[Mr Mower Man]

OK, I think I figured it out. Looks like somebody's been into this carburetor before. I compared the carburetor components with the diagram of the Keihin one barrel carburetor in the Kohler service manual. My carburetor was missing the slow speed jet, which explains the symptoms.

Thankfully, I discovered what I believe is the slow speed jet for this carburetor, part number 24 337 01-S. I only found this by doing a search for "CH20 idle jet" on ebay, hoping to find a used jet or something that would allow me to avoid buying a whole new carburetor (this is a used unit I bought, by the way). Could someone please enlighten me as to how I could use Kohler's own literature to find this information? I'm not comfortable having to rely on ebay for my technical information.

[bgsengine]

Kohler has that in their Snap-On parts catalog online (I dont know if they still have guest login) and it requires Internet Explorer unfortunately - If you are a dealer you should have a login for Kohler website - the ARI version of their parts lookups woll not show individual carburetor parts - just a mention of "see some other area for parts" or something to that effect - which in their Snap-On parts lookup you would go to the carb detail to find the service parts and kits available for that carb.

[KE4AVB]

Isn't great when some else does that? It is so annoying trying to repairing that someone that didn't know what they were doing just leave out parts or miss assembly things. It just plain makes me at times.

Yes Kohler Plus is still accessible via IE using the guest log in thought they stopped again but it was a server setting on my Internet provider had set on my cable modem. I got that straighten out with a reset by them.

The slow jet is item 23 below. Really need the spec number to verify it the correct PN number as I was spec 64509.

[Mr Mower Man]

The model and spec is CH20-64631. I have been using Kohler Plus with Internet Explorer, and it doesn't show me any information about a slow speed jet for this spec, unlike what appears under the 64509 spec. I intend to call Kohler tech support in the morning to verify the jet part number.

And yes, it is aggravating. I don't care much for cleaning up the messes of people who work on stuff but don't ever really fix anything. The first thing I had to do was work on the #2 cylinder head, since there was zero compression and 100% leakdown through the intake. Something small evidently got into the cylinder, left some marks on top of the piston, bashed in the end of the spark plug, bent the intake valve and both push rods somehow, and escaped into the exhaust. After I got that fixed, I discovered the carburetor problem. So it looks like whoever worked on the carburetor also dropped something into the intake manifold in the process.

[KE4AVB]

The model and spec is CH20-64631. I have been using Kohler Plus with Internet Explorer, and it doesn't show me any information about a slow speed jet for this spec, unlike what appears under the 64509 spec. I intend to call Kohler tech support in the morning to verify the jet part number.

Cross Referencing...............

Look-up the 64631carburetor pn then searched it. From there used the part number the first two were superseded to then finally used the "where used" to locate other the specs. The 64631 and the 64509 are shown using the same carb so you could click on the 64509 and it would carry you to the diagram I posted. I still learning to navigate Kohler Plus myself. With this I am fairly certain the 24 337 01-S is the correct jet.

Mr Mower Man I now have a Kawasaki twin engine on my hands that is dropping a cylinder at start-up and then smooths out after a few minutes. First I had rebuild the carb. ($150 in parts alone from JD) Something I never seen is a completely worn in two choke shaft. Now that I got the flooding issue corrected I got find this cylinder dropping problem. Sometimes you got one thing to find two more problems.

One good thing has already came this project as I found a source where I can lookup the Kawasaski part numbers for the JD engines and can save those surcharges from now on. I also found pn for an item I have been looking for a few years now. I knew sooner or later I would find just had find the right OEM that was willing to sell it.

[Mr Mower Man]

Cross referencing...now why didn't I think of that? It works like a charm! I still think the 64631 diagram should be complete like the 64509 diagram, though.

[Mr Mower Man]

Mr Mower Man I now have a Kawasaki twin engine on my hands that is dropping a cylinder at start-up and then smooths out after a few minutes. First I had rebuild the carb. ($150 in parts alone from JD) Something I never seen is a completely worn in two choke shaft. Now that I got the flooding issue corrected I got find this cylinder dropping problem. Sometimes you got one thing to find two more problems.

One good thing has already came this project as I found a source where I can lookup the Kawasaski part numbers for the JD engines and can save those surcharges from now on. I also found pn for an item I have been looking for a few years now. I knew sooner or later I would find just had find the right OEM that was willing to sell it.

So, any idea why one cylinder won't run at startup? I have a customer with a John Deere 445 who has been complaining lately about the way it starts. Sounds like it may be a similar problem as your Kawasaki engine, even though his is EFI.

And can you reveal your source for JD/Kawasaki parts lookup?

[KE4AVB]

So, any idea why one cylinder won't run at startup? I have a customer with a John Deere 445 who has been complaining lately about the way it starts. Sounds like it may be a similar problem as your Kawasaki engine, even though his is EFI.

And can you reveal your source for JD/Kawasaki parts lookup?

From the tune up this mornimg Ash Fouled #2 plug. I suspecting after several years of commercial use it losing #2 like many of the Briggs I have seen.

See my note to you...