W8ye,

thanks for the info. Some questions, and then comments. What is a "28" size carb? And what is the (#16)?

Glad it wasn't my imagination that Walbro's site is deficient. Maybe that guy you know at Walbro could put in a word that a new site is needed?

I'll try to get a WT-456 to start with. Another idea occured to me. Besides having oil clog the pulse tube and eventually the pump diaphragm, I've noticed that the engine crank rotation is severely restricted when the pulse tube is connected. This will rob horsepower due to piston backpressure. It also would inhibit blowby, possibly leading to bearing failure. So.....here's the idea: Add a tee to the line, with a tiny bleed screw. Adjust the screw slightly open just enough to get about 4-6psi (measure this) at the regulator, and the rest is vented to ambient. This is a compromise solution, but might relieve the crankcase backpressure enough to prevent performance loss. Comments?