Quote:

... and another small screen where the rubber fuel hose intersects with the fuel tube that adjoins both carbs.


Hey, Ken... you've been around here long enough to probably know that what Ryk is talking about has often been referred to as the 'hidden filter.' I concur with Ryk... check and eliminate that little sucker and install an in-line filter such as one from the great line of filters from erle. And again in accordance with Ryk, pull the petcock and inspect the mesh filter there for any signs of contamination.

And if all that fails, consult with Brent (BCarnage) who's years with the Muddy River Nightmare Band might just shed some light on the subject (because a muddy creek is pretty close to a muddy river, don't you think?!)