Fuel pump..electric and mechanical
#1
Fuel pump..electric and mechanical
Hey guys.
I'm currently running a holley blue electric pump on my car. The thing dies every two years or so, and i'm getting tired of getting stranded because of this.
My question is, can i run the blue electric pump along with a mechanical up front? I would still use the regulator set at 6psi. This would make the electric pump a helper pump, and if it dies, would the mechanical still be able to suck through the blue pump to keep me on the road?
Thanks!
I'm currently running a holley blue electric pump on my car. The thing dies every two years or so, and i'm getting tired of getting stranded because of this.
My question is, can i run the blue electric pump along with a mechanical up front? I would still use the regulator set at 6psi. This would make the electric pump a helper pump, and if it dies, would the mechanical still be able to suck through the blue pump to keep me on the road?
Thanks!
#2
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
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Re: Fuel pump..electric and mechanical
Mechanical pumps don't do so well sucking through dead electrics.
#4
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Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: Fuel pump..electric and mechanical
If your car still has a dead in-tank pump that your blue pump is trying to pull through - that is what's killing it. Might as well drop the tank and just replace the intank pump, skip the blue, and use a Mallory 4309 regulator.
#5
Re: Fuel pump..electric and mechanical
No, my car stock was with only a mechanical, and it suffered massive vapour lock when i swapped the 350 in. The blue electric cured the problem, but it's not very reliable.
I realize the mech pump won't like sucking through a dead electric, but will it let me limp home??
I realize the mech pump won't like sucking through a dead electric, but will it let me limp home??
#6
Supreme Member
Re: Fuel pump..electric and mechanical
The issue you're having with the Holley Blue pumps is that you're supply line to the pump isn't large enough. These pumps are not designed for lift but rather for gravity feed. Also, regardless of what the instructions may say, these pumps must be mounted vertically, motor up. I run mine with AN 10 to the tank and have it mounted below the tank. I also convert the dead head style regulator to a bypass style, as used in alcohol applications. This greatly reduces stress on the pump.
My Holley Blue is 8 years old and has never had an issue. Ive installed several in customers' cars over the past several years and have never had a single one comeback.
My Holley Blue is 8 years old and has never had an issue. Ive installed several in customers' cars over the past several years and have never had a single one comeback.
#7
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Car: 1991 Chevy Camaro RS w/t-tops
Engine: BBC 396 .090 over (414)
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Axle/Gears: Shortened Ford 9, 3.25, discs, posi
Re: Fuel pump..electric and mechanical
Question: I'm running a mechanical pump on my big block, im keeping the stock tank and location, how should I run my lines for a pick up? I'll be using stainless lines, but that doesn't really matter, should I like remove the stock pump sucker from the in tank unit and just have it suck up fuel? Help would be great!! Thanks!!
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#8
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Re: Fuel pump..electric and mechanical
What I did was leave the stock unit in place for the level sender and modified the outlet tube for use as a return along with the OE return. Then I installed an AN10 pick up tube using a bulkhead connector and fastened it to the OE pick up to be sure it sits about 1/2" from the tank bottom. I have a high flow filter between the tank and my Holley Blue supply pump. You could use the same basic design for your mechanical pump.
#9
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Re: Fuel pump..electric and mechanical
Bypass regulators are always the best way to run an electric pump. The pump never has any load placed on it and any fuel the engine doesn't need is returned to the tank. You could also feed the return back to the inlet side of the pump for simplicity and plumbing.
Since you're only regulating it to 6 psi, a red pump would also work as it's already self regulated.
Since you're only regulating it to 6 psi, a red pump would also work as it's already self regulated.
#10
Re: Fuel pump..electric and mechanical
I messed around a great deal with the fuel system of my car and found that holley blue pumps are junk. They sell alot of those rebuild kits.
Go good quality mechanical. I like carter or gmpp pumps or a carter carb electric with a mallory 4309 but you'll need to make a 3/8 return line if you go this route.
Go good quality mechanical. I like carter or gmpp pumps or a carter carb electric with a mallory 4309 but you'll need to make a 3/8 return line if you go this route.
#11
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Car: 1990 RS
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Re: Fuel pump..electric and mechanical
So a regular autozone/ advanced auto parts mechanical fuel pump in conjunction with a ac delco in tank fuel pump will not work??? I was using this set up and it worked fine up until I did my t56 swap and I fouled all my plugs because my air fuel mixture screws were screwed up...so I disconnected the in tank fuel pump and tried mechanical only and can't get it to run for nothing...should I reconnect my in tank fuel pump and hope it don't flood my engine???
#12
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Car: 1984 Z28 Hardtop
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Axle/Gears: 3.54 Dana 44
Re: Fuel pump..electric and mechanical
You won't flood the engine if the regulator in the mechanical pump is working.
#13
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Car: 1990 RS
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Re: Fuel pump..electric and mechanical
Wait wait wait! There's a regulator in the mechanical fuel??? When did this happen lol? I have a external regulator between the intank pump and mech pump? I just replaced that fuel pump so it practically new...so your saying I don't need my external/inline regulator???
#14
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Car: 1984 Z28 Hardtop
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Re: Fuel pump..electric and mechanical
Of course there is, that's how a mechanical pump works on its own without an external regulator.
#15
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Re: Fuel pump..electric and mechanical
Ok i never thought about it like that...which brings me to a whole nother heep of questions...if the mechanical pump is regulated how does my oil smell like fuel...and will regulating it thru the mech pump and a external regulator cause the engine to not ru-n...???
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