I hope I have the right forum for this question-Anyway, I have a 350 Chevy with a Holly Model 4160 600 CFM carb., vac. secondaries. I recently put a rebuild kit in and can't seem to fix this problem. The engine idles perfectly and runs out very well. When you shut down the engine gas continues to run into the secondaries and leaks out around the throttle shaft. You can remove the inspection screw in the side and the is no gas over this level so apparently the needle valves are working properly. Until the pressure from the electric fuel pump is releived this leak continues. Any ideas??
Thanks!

 

To anyone who has experienced similar problems, I have found that putting a pressure regulator in line and reducing the 6 lbs of line pressureto 2 1/2 lbs solves the problem. WAHOO!!