Kohler 23hp stuttering

[fmints]

Bazoo Guy: There is new fuel lines and filter, and I cleaned the tank,,, which was done between FEB and APR this year. I also have an additional electric fuel pump, and the problem still persist even with the electric pump on.

Mike: The 90 degree elbow is stock, but i will remove it since this motor's previous application didnt have a need for high rpm's. So you think that its not getting enough air?

JP: I hope its not a coil, it could be,,,, but if it is why is there fuel on the plugs?,,,,, Oh,, the fuel not being fired. I'll have to test the coil then!

Dwayne: The exhaust,,,,,,,,,,,, there is a section of about 3 inches that the size is reduced in a 90 degree curve on both heads. So maybe those sections is not allowing the exhaust to exit quick enough and the fuel is being stock piled in the cylinder, thus running rich, stuttering and hesitating (wet plugs).

[Dwayne]

Hi I will post you a post a comment I made about a similar problem the only way to try it is un bolt exhaust . The first symptom is motor running rich when you are full throttle Hi sounds like you having frustrating time .I fill like a goose but this is what happend what makes it worse is I build race engines for motor bikes. My max11 was brand new 2011model kolar 23hp had done about 120 hrs motor started running a bit strange lacking power then sort of come good but slowly got worse started flooding run alright with air filter off then wouldn't rev up with it on started spitting fuel out top of carby so the problem slowly got worse . So I pull motor down looking for sticky hydraulic lifters or brooken decompresser on cam witch I found they don't have .put motor back together problems stile there then a thought took off exhurst presto runs like a beauty .Cut exhurst open to stupid plates spot welded come lose block up exhurst well I fill like a goose with four other mechanics trying to figure it out .Give this a try you may be surprised

[jpswift1]

Drain the tank and start with fresh fuel.
Make sure the lines and filter are not leaking.
Check that you have good flow from the pump.
The fuel mixture shouldnt change....ignition could be breaking down at high rpm.

Possibly an issue with the coils?

[Bazooo guy]

Drain the tank and start with fresh fuel.
Make sure the lines and filter are not leaking.
Check that you have good flow from the pump.
The fuel mixture shouldnt change....ignition could be breaking down at high rpm.

[Mike]

One other thing to try before you start adjusting the mixture: Unbolt the 90 degree elbow on the carburetor and run it without anything there at all and see if it still stutters.

[fmints]

dont know about kohler, but i have seen briggs hide the air mixture screw by putting a plastic cap into the bore of the screwhole covering the screw.

That's great info,, I'll Check tomorrow!

[crashingone2002]

dont know about kohler, but i have seen briggs hide the air mixture screw by putting a plastic cap into the bore of the screwhole covering the screw.

[fmints]

Hello Gents, I recently finished rebuilding my Kohler 23hp. It idles and runs great except when you occasionally hammer on the throttle, it stutters like its getting too much fuel (flooding). The air cleaner is clean and good. Im only running the factory mechanical fuel pump mounted on the valve cover. I pulled the plugs and they are indeed wet with fuel. Ok so I found the problem, so I think! So next, I look to the manual for the fuel mixture screw, I think I found it, but when I look at the carb,,, I dont see it. I would really hate to tear this thing all the way down again for a simple fix. My question,,, Where is the fuel mixture screw? What side of the carb is it on. What else will make it run rich on the top end when the RPM's are up (3400-4000 rpm's)? Any suggestions?

Here are pics of the carb on all four sides:



2012-06-21195547.jpg picture by fmints - Photobucket
2012-06-21195547.jpg picture by fmints - Photobucket