Will only run when warm

[Apollos7]

I got it! First pull; it runs great. I think it was the bowl mounting screw. I’ve cleaned several times, but this time I ran a torch cleaning tool through it. Even though I soaked it in parts cleaner and sprayed it and blew it out before, I still got some dirt out of it. I also suspected the o-ring around the intake tube. The plate that the carburetor bolts to is pretty flimsy. I clamped a pair of vice grips on the flange where it is thinnest on top while I tightened down the mount bolts. Thanks everyone for your help!

 

[slomo]

You don’t happen to know what the main jet size is, do you?

Shouldn't worry about sizes as they are not sized. One jet for that carb only. Unless there is a pilot jet hiding under a welch plug??

 

[Scrubcadet10]

only a high altitude jet or stock.

 

[bertsmobile1]

Have you checked the intake manifold ?
To pretend the engine is cross flow B & S use a very long induction manifold from the carb side to the exhaust side where the valve is.
These were originally aluminium but that caused overheating so they went to a thermo setting plastic.
BEcause it is thermo setting it gets hard & brittle over time & heat cycles which leads to cracking and air leakage

 

[artemjemmy]

You don’t happen to know what the main jet size is, do you?

probably around 20 thousandths