10 years old, replaced the carb in 2006 at the suggestion of a Lawn Boy
repair shop. Original plastic carb, throttle shaft sticks disabling the
governor. New carb was redesigned supposedly to cure this but 4 year later
running into the same problem. The plastic carb is warping when tightened
down making either the butterfly stick of the shaft or both.

Temp cure is to loosen the mounting screws (two philips heads) to free up
the throttle shaft so the governor works. That allows it to be used but
the engine revs back and forth telling me the shaft is still a bit
sticky. Any looser bolted to the motor and it will suck air at the gasket
and not run right.

What to do...

Option 1, sand the carb flange with 1000 grit on a flat surface to make
sure it is flat (like milling a car motor head) ? Over-bore the throttle
shaft ever so slightly so if the carb flange warps when tightened it
won't seize the shaft? Widen the venturi around the butterfly so if it is
seizing when the carb is tightened it won't seize? All the above?

I'm tired of ****ing with this POS. My kid mowed this morning and except
for the wide open initial rev (2 seconds) when started and the govenor
oscillation when there is no load on the motor, it actually ran well.
But i know as soon as it sits for a while, maybe a week or two, I'm going
to have to **** with it again.

Your thoughts (besides buy a new mower);