Do I need an electric fuel pump!

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DoubleDingo

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Hmmm. I have the same problem. Fresh rebuild, edelbrock intake, Holley 4175 (quadrajet replacement) ... If I start it every day, fires up no problem. Wait a week before starting and ... Pump-Pump-crank-crank-crank-pump-pump-pump-crank-crank-crank ... etc. I know there is plenty of fuel in the bowl, because the last few times, before starting, I popped the hood and manually operated the throttle. Squirters squirt fuel. There is a clear external fuel filter and, as far as I can tell, the fuel is draining back through the (new) mechanical fuel pump. If the filter is full of fuel, truck starts right up. If filter is mostly empty, it takes several attempts to start.

I used to have a 69 Chevelle with a built 35o, Weiand intake and Holley double pumper. That thing could sit for 6 months and it would fire up on the second cranking revolution every time (in fact, my father-in-law used to brag to people about it).
My '81 is the same, let it sit and it takes a few to get her fired, but drive daily and it's a tap of the key.
 

Walstw01

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What fuel pump do you have on it? A 3 port has no check valve in the return and they can bleed back. But if there is fuel in the bowl and you have accelerator pump shot it should fire,have you actually looked at the accelerator pump shot? Or just heard it and saw vapors?
I removed the air cleaner lid and manually operated the throttle level ... actually saw streams of fuel coming out of the squirters. No return line on the fuel pump, BTW.
 

Ricko1966

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Is your choke working?
 

Walstw01

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(Electric) choke is working, but the fast idle is NOT working.
 

Ricko1966

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Hmmm. I have the same problem. Fresh rebuild, edelbrock intake, Holley 4175 (quadrajet replacement) ... If I start it every day, fires up no problem. Wait a week before starting and ... Pump-Pump-crank-crank-crank-pump-pump-pump-crank-crank-crank ... etc. I know there is plenty of fuel in the bowl, because the last few times, before starting, I popped the hood and manually operated the throttle. Squirters squirt fuel. There is a clear external fuel filter and, as far as I can tell, the fuel is draining back through the (new) mechanical fuel pump. If the filter is full of fuel, truck starts right up. If filter is mostly empty, it takes several attempts to start.

I used to have a 69 Chevelle with a built 35o, Weiand intake and Holley double pumper. That thing could sit for 6 months and it would fire up on the second cranking revolution every time (in fact, my father-in-law used to brag to people about it).
Okay get a piece of fuel line a bolt and 2 clamps. Next time on shut down, pull the rubber line off the inlet side of the filter. Cap the filter with the hose and bolt. See if it starts and runs out of fuel next time. That will confirm nor dispell fuel bleeding back from the pump. If you still have an issue,I,d be suspecting,carbureator internal leak. You have just enough accelerator pump shot left to be visible and no fuel left in the bowl to run the car.I am not familiar with the Holley 4175 see if it has the option of windowed or not windowed needle and seat. Try a non windowed needle and seat.
 

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