Leak at Accel Pump Stem

[von]

Q jet # 7028218, '68 Chevelle 396 350 hp automatic. Carb restored about 2 yr and 2k miles ago. Gas is seeping up around around the accelerator pump stem at idle. Seems to be running rich too and wants to die. At a show I took the top off and installed a new float, needle and seat, accel pump cup (blue), seated the check ball with a punch and light taps, and installed new check ball and top gasket. Set float level at 1/4". Still doing it. Any ideas?

[Cliff Ruggles]

A high fuel level indicates a leak past the inlet needle.  Could also be leaking around the seal under the fuel inlet seat assembly.

High fuel pressure will cause this to happen.  Assuming new parts were installed, and the parts are sealing up correctly, float level correct, etc, take a look at high fuel pressure......Cliff

[von]

Thanks for the reply. I was trying to fix this for a friend at a national Chevelle show. The accelerator pump looked like it may be too short. At WOT the top was slightly below the casting and at rest it was shorter than a like carb also. I'm wondering if it's possible the wrong accelerator pump, being too short, could hold the cup up in the tapered part of the pump bore and cause a leak?

[Cliff Ruggles]

The length of the pump could be wrong, but not cause a leak around the accl pump shaft being out of the bore.  Some fuel can splash up and leak around the accl pump shaft, but if fuel is running out, the fuel level is too high....Cliff