Bought a Western Star 1979 Dump Truck and rebuild the PT pump. It was leaking diesel from the throttle shaft. I got a rebuild kit and replaced the bearing, seals and o-rings and the AFC bellow. After I put the pump back in the truck it had very low power. I was trying to figure out what is going on and tried adjusting the no-air screw and voila I opened it half turn then the truck had more power. When rebuilding it I did not mess with that screw at all and it turned that it was only open one turn from full stop. Is there a rule of how many turns the AFC screw should be unscrewed from full stop?? Thank you!
Needs to be adjusted on a test bench by injection shop, other wise it's shooting in the dark. No two pumps are the same when assembled. Normally a injection shop will set that at 10% over stock setting but in order to adjust properly it needs to be done on a test stand. Plus rail pressure can be seen.
Thank you! I will look for one around here in Vegas.