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voodooskin

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Dec 28, 2022
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Location
northwest
First Name
Voodoo
Truck Year
1985
Truck Model
K2500
Engine Size
5.7L
I have a pretty horrible setup on my '85 square / dual tanks. It has a new factory 5.7L crate motor installed by the previous owner, there's a mechanical fuel pump on that motor, Edelbrock carb. Under the passenger side there's an electric fuel pump added, it must be between the fuel tank selector and the motor.
This is it cleaned up, it was covered in grime. The electrical leads press on and take so little force they almost fall off (the PO admitted the truck got stranded once due to a lead falling off).
I am new to this truck and have never been a GM person so its all new - why the electric fuel pump in the first place if there's a mechanical on the block?
Anyway, looking to replace it with something like:

https://www.amazon.com/gp/product/B07ZNS6WQR/ although the cheap price gives me pause or

https://www.amazon.com/dp/B08WHV3FTD/ the more expensive facet pump probably similar to one mentioned earlier

This pump screams when it's first fired up until it runs a bit esp. when cold, the passengers in the truck freak out. Super loud, pretty quick/dirty install
 

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Ricko1966

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Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
If someone has added an electric pump to your truck that came with a mechanical pump.the electric pump is probably masking a bigger problem.
 

voodooskin

Junior Member
Joined
Dec 28, 2022
Posts
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Location
northwest
First Name
Voodoo
Truck Year
1985
Truck Model
K2500
Engine Size
5.7L
I don't know how these trucks come OEM. In my case, the motor got replaced last year with a factory crate at 90k miles, the former owner's kids were driving it and never checked the oil (life lesson there). He's a friend, no issues with disclosure.

I've seen some posts here where replacement motors don't have the mechanical fuel pump. In my case, it's there. So no idea on the electric unit other than the install of that unit seems pretty quick/dirty: the wiring to it is organic and unprotected and the pump squeals for a few minutes on startup esp in the cold, seems wrong.

I don't mind replacing the electric unit with a better install, but worth an ask why there's a 'boost pump' at all. Maybe I should try just removing the electrical pump and see if she runs only on the mechanical one......
 

Ricko1966

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1975
Truck Model
c20
Engine Size
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You shouldn't need an electric pump at all. Unless it was installed as a crutch for a different problem. If the fuel pump pushrod behind the pump moves in and out about 1/2 inch with the engine cranking,you don't need anything except for a good mechanical pump can't beat them for the money. They the job well and they are cheap and reliable. I'd pull the factory pump and the mounting plate. The pushrod is right there,pull the power wire off the distributor cap push up on the pushrod and have someone crank the engine. Does the pushrod go in and out? Great put a good pump on and ditch the electric.
 

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