topcat,
You sure have covered all the bases. I have several rigs at work with the clear filter ahead of the carburetor. None of the filters ever fill more than 1/2 full, yet the engines run fine.
I have always thought there must be a air cushion, or some time of self leveling effect going on. The carburetor cannot suck gas, it must be pumped in by the pump.
The cam lobe could be worn, but the bog on acceleration probably is a tuning issue, or a carburetor adjustment issue. The fuel pump is sort of a 'it works' or 'it doesn't work' kind of deal.
Installing the clear filter might have given rise to a problem that isn't really there.
A easy test would be to pull the discharge line from the pump and see how much fuel it moves.
Stuart
