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I keep getting air in my fuel line; can air get in without fuel leaking out? It 6an from the carb to the fuel pump with a filter in between and 1 foot rubber hose to the tank. It’s a stock 68 camaro tank. It jumps around between 3 and 7 like crazy and drops to 0 on occasion for like a min then it will come back up. I have had to bleed the fuel line before at the carb. I’m scratching my head with this one any help would be greatly appreciated.

I believe you are going to find your problem to be the pump. It sounds like it is bleeding down with an internal leak like a bad diaphragm. Do you have any gas in the oil?

There is no fuel in the oil, My first thought was the pump i replaced my holly red with a holly 125 with no help.

Is it a stock pump or an electric

If one has an air leak before the pump, it will not suck..will stop pumping
If adter then the fuel will leak out.
It is not unusual to have 'air' bubbles in the line..it doesnt mean its air.
This is a very common question or worry that pops up when dealing in very old cars..pre 50s 60s.

The pressure variation could be the gauge, espec if it is a fiuld filled gauge.

When switching fuel pumps, did you replace the fuel filter??? If it's been in the fuel system for several years it could be partially clogged causing the erratic pressure readings at the gauge.

David F.

Thanks for all your help but i think I stumbled across it laying under it the other night. My fuel pump mounted higher then the bottom of the tank. If i keep my tank over half full i dont seam to have a problem. steady 6 1/2 lb next step fuel cell with a return line but thats going to have to wait tell winter.

That is an indication you have a very slight air leak on the suction side of the pump. and/or the non return valve in the pump is failing.