Chadborne

Bought a 1970 454 that has a 4165 holley. The carb was not on the engine when I got it, but when mounted the back two ports flood. Have replaced most parts internally and doubled checked the bowl and float, including the needle. They all seem to work fine. I have bent the lever that pushes the needle to a point to cut off all gas flow and the engine runs but w/o the back two ports. I did have to install a new fuel pump when I found the one that came with the car did not work. Could it be providing too much pressure? If you don't have any suggestions on fixing the problem, what carb would you recommend as a replacement?

DC3

I had a very similar problem with my Holly 650 DP. Took awhile to diagnose the problem but the previous owner had put on a non-stock fuel pump and I was getting too much pressure at the carb. Replaced the pump with a stock unit but that didn't completely solve the problem. I also ended up having to replace both the primary and secondary floats as they would not maintain proper fuel level even with the new pump. I am only guessing that too much fuel pressure over time weakened the spring mechanism on the original floats so that even a stock pump was blowing fuel by them. Anyway, after replacing the pump and the floats, the fuel levels stay where I set them.

DC

Chadborne

Thanks for the suggestion. I might try to find new springs and see if that helps, before trying to find new bowl assemblies.

burners

How did you check the float and needle? It may be worth replacing the needle valve. Also, how are you setting the float level. Are you using the sight plug? Too much pressure only makes since if both from and back are flooding. Do you have a fuel filter on it?

Chadborne

I removed the bowl and adjusted the float and checked the needle for wear. The front bowl and the fuel spray in the front ports are ok. There is no site plug on this carb. There is a fuel filter. Too much pressure makes since to me as well.