Dave,
The most likely problem with the accelerator pump would be one, or both, of the check valves are inoperative or missing.
I think the one in the float chamber is a "reed" type valve. The one under the delivery port is a ball bearing.
The fuel pump should have the capability to pump excess fuel volume to the carbs. Since it is a common delivery system, fuel should be pumped
to both carbs until the floats close both needle valves. If you are experiencing a fuel deficit to the rear carb, you should check for an obstruction
between the line junction to the first carb and the rear carb's needle and seat. You might possibly check the fuel pump output.
Hope this helps,
Hi guys, this will be one of many questions I'll have now that my car is up and running. It seems I can't get the correct amount of fuel to the rear carb. It runs pretty well, but with the air screens off and I rev it up, there is no fuel coming from the accelerator jet, and very little from the main jet. Front carb is fine. Both carbs were fully rebuilt, and I dismantled the rear carb again and found nothing wrong. Float level was good, all passages clear. Idles fine and seems ok on the road. With the carb top off, I pushed the accelerator piston multiple times and no fuel discharge. Any thoughts? Dave
Are we talking WIA or WIP Zeniths ?