Do I need an electric fuel pump!

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Barrett-FL

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I just purchased an 86 C10 with a 350 and it runs great and starts at the turn of the ignition…that is if I start it every day, however, if I let it sit for a couple days I have to crank and crank to get the fuel filter to fill up and get gas to the carb. Once the filter is full it will start perfectly but after a couple days of not being started the issue repeats.
Do I need to install and electric fuel pump to have it always start right away and not wear out my battery and starter?
Thanks for your help!
Barrett
 

Ricko1966

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You shouldn't need an electric pump,they didn't need them new. What carbureator and fuel pump do you have. Should be quadrajet and a 3 port mechanical pump. Check and post back
 

DoubleDingo

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I just purchased an 86 C10 with a 350 and it runs great and starts at the turn of the ignition…that is if I start it every day, however, if I let it sit for a couple days I have to crank and crank to get the fuel filter to fill up and get gas to the carb. Once the filter is full it will start perfectly but after a couple days of not being started the issue repeats.
Do I need to install and electric fuel pump to have it always start right away and not wear out my battery and starter?
Thanks for your help!
Barrett
Nope. Mine does the same thing. It doesn't wear out the battery or starter, just give it the full press before turning the key, turn it over for a second or two, give one to two pumps, and do it again. If it doesn't start, only one more pump, and try a third time.

I may get blasted for it that way and suggesting here, but I hate dry rotating an engine, so I try to get the fuel in the carb quickly, and less rotating with the starter and faster firing
 

fast 99

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Think about it this way. How many new trucks would have been returned to the dealer if this was normal? GM did not install electric pumps; they didn't need it.

However if they sit for a few days fuel will evaporate from the carb. Could also be fuel leaking out of Q jet well plugs, weak pump, fuel drain back or choke issues.

All of my carb vehicles have extended cranking after sitting a few days, not horribly long may be 5-10 seconds. That's normal.
 

DoubleDingo

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Think about it this way. How many new trucks would have been returned to the dealer if this was normal? GM did not install electric pumps; they didn't need it.

However if they sit for a few days fuel will evaporate from the carb. Could also be fuel leaking out of Q jet well plugs, weak pump, fuel drain back or choke issues.

All of my carb vehicles have extended cranking after sitting a few days, not horribly long may be 5-10 seconds. That's normal.
^^^^^^THIS^^^^^^
 

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Common for carbs that sit for extended periods. Elec. pump as a primer will fix it. Or borrow that little squeeze bulb off one of your chain saws!
 

Ricko1966

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If it has a windowed needle and seat with a leaking needle and the incorrect or no fuel filter installed it will do this. It will bleed the bowl dry through the return line.
 

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Doesn’t need an electric fuel pump. But not normal for sitting a few days or weeks or months. Needs a little carb work sounds like.
 

Barrett-FL

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Thank you all for your replies!

The carbonator and intake manifold are Edelbrock.

I was thinking of having the electric fuel pump as a primer as Copymutt suggested.

Not sure what a "widowed Needle" is.
 

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Matt69olds

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Windowed style on the left, solid on the right.
 

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vintovka

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Someone said running a electric BEFORE the mechanical affected the diaphragm in the latter. Not sure how it would work with electric after mechanical for start ups. Mine now starts fine with just the Mechanical and one pump before starting.
 

Ricko1966

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Someone said running a electric BEFORE the mechanical affected the diaphragm in the latter. Not sure how it would work with electric after mechanical for start ups. Mine now starts fine with just the Mechanical and one pump before starting.
Electric pump before the stock mechanical pump is just fine. If you use an electric pump,with no anti siphon valve or anti drain back valve the electric pump doesn't even need to run full time fuel will free flow through it. So a monetary contact switch,push the button,prime the system,release the button start your car. You do not want to mount an electric pump far from the tank ,and you want to keep it below fuel level. Pumps push better than they pull.When I mount one I angle the pump so the outlet is slightly higher than the inlet so the pump always has fuel in it,preventing dry starts. A facet 40106 would be a good choice as a primer pump. They are USA made and ethanol compatible,they are very noisy though so just use as a primer pump.
Edit, when running an electric pump solo, I blow through a factory pump on the engine block, no pushrod behind it. That way I can use all my factory hardlines,fuel supply, carbureator supply,and return. If running an electric pump,solo this way you may have to put a restrictor in the return line to keep from bypassing too much fuel.
 
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Walstw01

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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).
 

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).
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?
 

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