Agra Fab Leaf sucker

[JeffreyOwens]

I have an Agra Fab Leaf sucker (I know that's not the right name just cant remember). Anyway the problem is that when running the exhaust turns cherry red it will also back fire thru the carburetor when turning off. Is this a timing issue or what else could it be. It is a Briggs & Stratton engine. Thanks in advance for any help.

 

[DJ54]

Running lean usually makes them run hotter.

Is there a throttle on it to idle it down to cool itself for a while, before shutting it off..?? I've seen a few people shut engines down hot, from WOT, and do this. Then, in a few years wonder why they don't run right, or at all.

I'd imagine it is so hot on shutdown, if the exhaust was cherry red, it's igniting fuel vapor brought in, when dieing down, simply from the heat alone. Doubt it has a fuel cut off solenoid, so it keeps sucking fuel in. All you are doing is killing the spark, not fuel, into the cylinder, and popping back through the intake valve.