Kohler carb repair

This is a revolving customer. 2nd time for same issue. Simplicity rider with 15 hp Kohler.

I have cleaned carb well, replaced fuel lines, and replaced fuel pump.

Under the shroud is clean. There is a rust stain on the kill wire near the coil. I plan to put a hose on the wire to insulate it for sure.

When mowing, it will stall and backfire. I mowed with it for an hour and couldn't get it to do it for me.

It has a fuel shut off solenoid and a manual fuel shut off valve. I left the valve open and when I tried starting it, it was vapor locked. When it did start, the exhaust exit was wet with fuel. The oil level is perfect.

I removed the carb, removed bowl and turned it upside down. I blew it dry with air. When I crank engine, fuel gets past the needle. I do not think the fuel is getting thru on the outside of the seat. I think I see fuel getting past needle without cranking engine.

I plan to change the brass seat and needle with part 1252104. I want to tap 1/4 x 20 threads in the old seat and remove it with a bolt. Then, press the new one in with a vise and short step bolt.

Anything I should keep in mind during process?

Are there any other tests I could try?

The rider is in decent shape and I never have this much trouble with Kohlers.

thanks

Well, I was suprised by results. I got new seat in and when I cranked the engine, no fuel went past the needle.

The kit was pricey at $30 but included all the gaskets for carb.

It came with a sheet metal screw to remove old seat. I screwed it in and the seat was supposed to come right out. Yeah, right! I had to clamp screw in vice and gently tap on carb with a rubber mallet to get it out. I tried using a cheap drill press to press the new seat in. I got it in 85% of the way and had to gently tap it in the rest of the way with a hammer. It came with a plastic block to protect the seat. I lost the block and hammered my thumb!

I will let it sit overnight to see if it leaks tonight and locks the engine up.

I think it is ready to go.

Don't use hose to insulate wires. Automotive hose has carbon in it and is therefore cunductive. Saw a bodyshop wiring repair with vacuum hose wiring "insulation" almost catch a new Caddy on fire.