The Car Care Clinic with the Dr John

72 351 C Ford V-8 - fire comes out of the carb

Charlie from Leeds

Question

I have a 1972 351 C Ford V-8. It has headers and a 750 Holley carb. The car has been sitting for 5 years. My problem is that if the RPMs are gradually raised it's OK but open the throttle quickly and fire comes out of the carburettor. After running at idle for a while it will start popping out of the exhaust like it's loading up. Raising the RPMs up for a bit seems to clear it up and the vacuum gauge is steady at 20 but any quick wide open throttle from idle again will pop through the carb. It’s loading up with way too much fuel. I can't understand it.

Answer

Chuck, Your problem is likely with the carburetor. Letting a Holley carb go dry for so long causes the gaskets inside to shrink and fail. Have the carb cleaned and rebuilt. That should turn your flame thrower into a tire burner instead.

Good Luck!
Dr. John