Briggs 12.5 I/C Carb Mixture Screw

G'day guys,

My engine is overfuelling a bit/running rich, was just wondering which is the mixture screw on my carb so i can lean it out a bit

Thanks

Depends how old it is- after the 90's most motors come with a 'bolt' instead of a mixture screw ( EPA stuff) - the screw on top is for the air- the screw on the bottom of the float bowl is the fuel - usually a good rule of thumb is turn it all the way in till it lightly bottoms, then turn it out about 1 1/2 to 2 turns, start the tractor and adjust it till it stumbles, then back it off a turn.

Before doing that it might be better to clean and possibly get a rebuild kit for it first.

I'd take it apart, clean it well, then stiack it back together. If it's rich it'll be the jet on the bowl (if its adjustable) Just turn that in a little at a time and see it it bogs under acceleration.

Thanks guys i'll have a look into it.
I'll get a photot of my carb and post up and if someone could name a few things on it for me would be great.

My rig is getting a full tear down and re-paint, bit of a freshen-up etc so the donk will get some TLC

One other question, is there an idle screw?...to drop the idle rpms

Thanks tyson

Yepper - when you look at it from the top- the first plate inside is the choke- then behind that further in is the throttle plate - when its activated, part of it outside contacts a 'stop' - theres a screw that will lower idle speed. If that wont fix it, it could be an issue with the governer or governer link....

What he said