Author Topic: Quality, reliable mechanical fuel pumps  (Read 777 times)

Offline Cadman-iac

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Re: Quality, reliable mechanical fuel pumps
« Reply #15 on: July 08, 2025, 12:15:13 AM »
make sure to retain the oil switch in the fuel pump circuit. it is usually just above the oil filter on the TBI trucks, but you can use the oil gallery under the distributor as well. this serves 2 purposes, 1. if your relay dies, once you crank enough to get above 5 psi, the pump will energize from the oil switch alone 2. takes load off the relay contacts for longer contact life.

also don't use regular fuel line in the tank,.you need to get fuel hose rated submersible. usually black hose with a pink stripe on it.

  Tayto,
 I lobotomized the computer once I decided to go with the carburetor. I removed the check engine light and replaced it with a choke indicator light.
 Unfortunately I couldn't make the pump relay work in conjunction with the choke and light. The electric choke coil  would draw too much of the current that the relay would not energize.

 Not sure why it didn't work, but I gave up trying and just wired the relay through a switch under the dash instead.

 Would you know how to get the factory pump relay to work through the oil pressure switch and also energize the electric choke and the indicator light?
 The only way I can see to do both is to use 2 different oil switches. Any suggestions?

 Rick
 

Offline Kenth

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Re: Quality, reliable mechanical fuel pumps
« Reply #16 on: July 08, 2025, 12:58:32 AM »
Good luck finding a quality American product for cheap.
For cheap you get a Chinese product no matter what it says on the box.
And yes, the box may be made in the USA but the contents may not.

FWIW

Offline Kenth

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Offline taguy4

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Re: Quality, reliable mechanical fuel pumps
« Reply #18 on: July 08, 2025, 09:56:12 AM »
Why couldn't you just use a Carter M4891 style mechanical pump with a Jeep Wagoneer fuel filter, which has a built in return line port? I never liked the idea of putting an electric fuel pump in the gas tank for a number of reasons, and external electric pumps have problems of their own, such as being able to put them in the best location and wiring them properly so they are safe.

Offline quadrajam

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Re: Quality, reliable mechanical fuel pumps
« Reply #19 on: July 08, 2025, 01:35:32 PM »
Cadman, check out revolution electronics fuel pump controller 12003.
Available from the mfg. or several other online sites. Made in USA.
about 75$. Doesn't need oil pressure logic, works from tach signal.
I have one but have never got around to installing it yet. Gonna
have to put it on the DO list.

QJ

Offline quadrajam

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Re: Quality, reliable mechanical fuel pumps
« Reply #20 on: July 08, 2025, 04:59:07 PM »
What does a choke indicator light do....????
I used the original key-on wire for the v6 distributor to power up the v8 HEI distributor,
electric choke and at times a fast idle solenoid. plenty of voltage for all 3.
Fuel pump is another circuit that goes through the oil pressure switch. There is no automatic
prime. I have a button on the dash for that.
Should take very little current to power a relay and choke heater....

QJ

Offline tayto

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Re: Quality, reliable mechanical fuel pumps
« Reply #21 on: July 11, 2025, 07:29:43 AM »
I'm fairly sure GM had a 3 wire switch that would do the fuel pump and oil pressure light (choke light). I will have to search. In my square body I actually have the TBI running everything but the injection. sure is nice to change timing with a couple key strokes and then flash it to the ECM

EDIT: i think this is the correct sender:
https://www.rockauto.com/en/moreinfo.php?pk=44300&cc=1143964&pt=4588

my experience has been they all use the same plug but only use 2 pins instead of 1, so should be easy enough to add the extra wire.
« Last Edit: July 11, 2025, 07:35:44 AM by tayto »