Briggs and Stratton RPM on snowblower

[ctatham]

I have an older 8hp horizontal shaft engine on a 26 inch Yard Man Snowbird blower (early 80's).

I recently restored it and rebuilt the carb. It seems to run well but it surges a bit when warm at high throttle. I am wondering if its is running at the right rpm (fast enough) and what I might do to get rid of the surging.

The governor was not touched in the restoration...which was mostly cosmetic. All new fuel line and filter were installed along with a new plug. High speed needle is adjusted as per the manual. The throttle arm goes all the way to the end of its available travel on the engine side.

Are heads worth pulling (gasket) on an engine that seems to run ok? Could the muffler be the issue? it sparks a bit when using it in the dark...but I figured that was normal.

oh, when first started cold on the choke it does smoke quite a bit...whitish blue....but the clears up quickly.