Craftsman Tractor

[lefty]

917.254940
SN: 2050S10533

Briggs: 303777-0015-02 / 90060613
According to schematic, the carb is 807639. I can't seem to find an aftermarket option.

Came with a choke only running condition. Didn't start when I got it. I removed carb and took the bowl off. Removed main jet and cleaned. There was dirt in the bowl. I cleaned the carb but didn't run through my ultra sonic. I squirted carb cleaner through the body.

I still have a running issue. It runs smooth for about 4 seconds and then drops and comes back up. If the choke is on 1/2 way, it will run smoothly. I know I have to take another run at the carb.

There's a plastic tube/straw coming off of a nipple on the carb running up above that I assume is a type of vent. When I put my finger over the end of the tube, it runs smoothly. I'm wondering if this tells me anything as far as where my problem is inside the carb. I'm treading carefully with the carb because there doesn't appear to be any aftermarket options and I can't find the kit either. The OEM also looks unavailable except for used and they're pretty expensive.

Thanks

[KE4AVB]

When cleaning a carb even in USC you must remove most metering components (jets, tubes, nozzles, idle mixture screw) so the ultrasonics can access these area easier. Even then you slightly open a main jet as it can develop slight layer oxidation. This why I have my micro drill bits.

I ran a carburetor Friday thru the USC multiple times and the first three 30 minute cycles, only so much would come out and stop. Upon the fourth cycle I saw none coming out. I describe this stuff coming as water smoke.

And be careful as Briggs don't supply parts like they use to. Basically Briggs is no longer the company that we can depend on.