CH20S question

[dropzone]

I'm working on a Kohler Family 3KHXS.6242GC, Model CH20S, Spec 64510, S/N 3319007311. I am looking for a Carburetor that will fit other then the factory carb. The carb on it was gummed up bad and I cant get it to run right. It idles fine and the high speed is good it's off idle that is giving me fits, I have soaked it 3 times over night sprayed it out with carb cleaner and blown it out with high pressure air from my compressor each time. This isn't my first rodeo but for the life of me I cant get this thing to work like it should. I am looking for a non emissions carburetor that will fit if there is a alternative. I do have two good carburetors off a 18 hp Briggs opposed twin if you guys know of an adapter that will work would be nice also. Sorry I don't have any other information on the Briggs carbs.

[KE4AVB]

Are you having acceleration problems? These carburetors have a mechanical accelerator pump that can give problems.

[dropzone]

Yes but it don't have an accelerator pump like the 25 hp. It has what they are calling a slow idle jet. It has a slow idle adjustment needle valve I found after a soaking in carb cleaner and the plug had fell out. I have rebuilt the carb or I installed a rebuild kit which wasn't much more then a needle valve, spring and rubber o rings and gasket. When I hit the gas it stumbles then picks up most of the time but some times it will die, then from full throttle when I let off it wants to idle way down. It idles perfect and full throtle is good it's just the in the middle. I have adjusted the idle air from bottomed out to 1 1/2 turns and went from there with no help. The guy I got the engine from left old untreated gas in it and the carb was in really bad shape. One thing I did do is remover the plunger from the fuel shut off but I cant see that causing the off idle acceleration problem. I feel this is just one of those things when a new carb is needed. Man I hate spending over $100 on a carb if I can make what I already have work. I may still try to build an adapter for the Briggs carb if I cant find something else that will work. I know both of them are in perfect shape.