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914World.com _ 914World Garage _ Fuel Pump Wire
Posted by: trojanhorsepower Nov 17 2019, 07:55 PM
So, I moved the fuel pump to the front of the car and ran a wire back to the engine compartment. What do folks do with the dangling ground wire? Same with the brake switch. Two wires one connector, so what did you do with the other wire?
Thanks
Peter
Posted by: FlacaProductions Nov 17 2019, 08:09 PM
My fuel pump ground runs up through the fuel tank access hole and grounds at the bolt that anchors the windshield washer reservoir.
Posted by: trojanhorsepower Nov 17 2019, 08:26 PM
Thanks, but I mean the one in the engine compartment.
Posted by: Spoke Nov 17 2019, 08:38 PM
The ground wire for the fuel pump can be connected to any chassis stud. Just make sure you scrape all paint/undercoating off of the area before connecting the wire.
Posted by: Highland Nov 17 2019, 08:54 PM
I don't think you need the one in the engine compartment. Just insulate it so it doesn't short against any adjacent hot wire.
At least that's what I'm doing unless the experts here say otherwise. 
Posted by: Jonathan Livesay Nov 17 2019, 10:21 PM
I don't think you need the one in the engine compartment. Just insulate it so it doesn't short against any adjacent hot wire.
At least that's what I'm doing unless the experts here say otherwise.
Yes, don't need it, ground is ground. Run a wire from the + side of the fuel pump plug under the engine shelf up through the tunnel and to where ever you have mounted your fuel pump plug it to the positive side of the pump and then just ground to the nearest ground stud (anything with brown wires connected to it).
Posted by: trojanhorsepower Nov 18 2019, 03:35 PM
Cool. Thanks folks!
Posted by: dr914@autoatlanta.com Nov 18 2019, 03:52 PM
should have run the hot and the ground together in a cable and connected to the fuel pump wiring harness pigtail in the right front of the engine compartment
Posted by: trojanhorsepower Nov 18 2019, 04:20 PM
George,
I considered that, but most folks felt it was unnecessary. I saw no reason not to ground it in the front from an electrical standpoint. Do you know of one?
Posted by: trojanhorsepower Nov 18 2019, 04:21 PM
A quick follow up. where do the wires come through the engine shelf? Is there a grommet? Any pics?
Thanks
Posted by: Chi-town Nov 18 2019, 04:49 PM
left side above the hood release handle.
Just for reference in case anyone looks to this thread for help.
DO NOT run a ground all the way from front to rear!
You can ground the wire at any point on the chassis itself.
Posted by: SirAndy Nov 18 2019, 05:10 PM
You can ground the wire at any point on the chassis itself.
And here i thought the FI brain was switching THE GROUND for the fuel pump on the relay board.
Posted by: trojanhorsepower Nov 18 2019, 05:52 PM
OK Guys,
Thanks for the input. Please note that I bought this car in boxes... There is a hood release in the engine bay?
SirAndy, so now I am confused. Which wire is the correct one, or should I run both? I have always read that I need to run the striped wire to the fuel pump and ground it locally, but you guys are making me second guess that.
When I look at the schematic it looks like the striped wire goes to the regulator plate (whatever that is) and the brown wire goes straight to the chassis ground. So, how would the relay switch to ground? I know this may sound dumb, but I don't know....
Posted by: SirAndy Nov 18 2019, 06:45 PM
OK Guys,
Thanks for the input. Please note that I bought this car in boxes... There is a hood release in the engine bay?
SirAndy, so now I am confused. Which wire is the correct one, or should I run both? I have always read that I need to run the striped wire to the fuel pump and ground it locally, but you guys are making me second guess that.
When I look at the schematic it looks like the striped wire goes to the regulator plate (whatever that is) and the brown wire goes straight to the chassis ground. So, how would the relay switch to ground? I know this may sound dumb, but I don't know....
Now that you mention it, i'm pretty sure the FI brain grounds the fuel pump relay, not the fuel pump ground.
Sorry for the confusion ...
Posted by: trojanhorsepower Nov 18 2019, 07:00 PM
Thanks Andy, I got it.
Posted by: jcd914 Nov 18 2019, 07:26 PM
Fuel pump wires go through the engine shelf below the battery tray and there is normally a grommet, probably old and hard and cracking. I think 914rubber has replacement grommets.
And yes the FI controls the relay so you only need to extend the power wire for the pump and ground it locally.
The factory used a larger gauge wire to the fuel pump when they moved it up front. The longer the electrical run the more resistance there is and so you need a heavier wire to carry the current for longer distance.
Jim
Posted by: JeffBowlsby Nov 18 2019, 07:46 PM
To relocate the FP to the front, follow the factory schematic for the 75-76 cars:
Use 12GA power wire from the 14 pin connector on the relay board (preferably black/red)
Use 12GA ground wire to chassis ground at the FP (Brown only)
Posted by: ClayPerrine Nov 19 2019, 01:07 PM
When I moved the fuel pump on Betty's car to the front years ago, I put some time into it and made it what I considered right.
The black/red wire comes from the relay board through the harness and over to the original location of the fuel pump. I pulled the wire back to the point where the harness turns to go up the tunnel, and routed it through there, following the factory harness. It made it to the heater control lever. I then spliced in a new section of black/red wire to extend it. I followed the harness past the pedals and up to the fuse block. At that point, I added a brown wire of the same gauge as the black/red wire and hooked it to the ground point above the fuse box. I then continued to follow the harness toward the front of the car, through the rubber grommet and down under the tank. I ran it across under the tank to the fuel pump, and put the factory plug back on the end of both wires.
It was a lot of work for just a fuel pump relocation, but it looks like it was installed that way from the factory.
Clay
Posted by: trojanhorsepower Nov 19 2019, 06:37 PM
Thanks guys!
Clay that is a lot of work but sounds good.
Peter
Posted by: trojanhorsepower Nov 25 2019, 07:19 PM
When I moved the fuel pump on Betty's car to the front years ago, I put some time into it and made it what I considered right.
The black/red wire comes from the relay board through the harness and over to the original location of the fuel pump. I pulled the wire back to the point where the harness turns to go up the tunnel, and routed it through there, following the factory harness. It made it to the heater control lever. I then spliced in a new section of black/red wire to extend it. I followed the harness past the pedals and up to the fuse block. At that point, I added a brown wire of the same gauge as the black/red wire and hooked it to the ground point above the fuse box. I then continued to follow the harness toward the front of the car, through the rubber grommet and down under the tank. I ran it across under the tank to the fuel pump, and put the factory plug back on the end of both wires.
It was a lot of work for just a fuel pump relocation, but it looks like it was installed that way from the factory.
Clay
Clay, I have been thinking about what you wrote. It seems like a good way to do it, but how on earth did you get the wire through the snorkel?
Peter
Posted by: ClayPerrine Nov 26 2019, 12:46 PM
When I moved the fuel pump on Betty's car to the front years ago, I put some time into it and made it what I considered right.
The black/red wire comes from the relay board through the harness and over to the original location of the fuel pump. I pulled the wire back to the point where the harness turns to go up the tunnel, and routed it through there, following the factory harness. It made it to the heater control lever. I then spliced in a new section of black/red wire to extend it. I followed the harness past the pedals and up to the fuse block. At that point, I added a brown wire of the same gauge as the black/red wire and hooked it to the ground point above the fuse box. I then continued to follow the harness toward the front of the car, through the rubber grommet and down under the tank. I ran it across under the tank to the fuel pump, and put the factory plug back on the end of both wires.
It was a lot of work for just a fuel pump relocation, but it looks like it was installed that way from the factory.
Clay
Clay, I have been thinking about what you wrote. It seems like a good way to do it, but how on earth did you get the wire through the snorkel?
Peter
Pull the harness out of the engine shelf and bend it until it is as horizontal as possible. You may have to disconnect the harness at the relay board and the ground point next to it to get enough slack.
Take a piece of aluminum thick gauge solid wire, spray it with silicone and feed it through the snorkel until it comes out in the passenger compartment. Make a loop in the end of the aluminum wire, put the black/red wire in the loop and pinch it closed. Use electrical tape sparingly to streamline the junction. Spray the junction and the black/red wire with silicone spray and pull on the end of the aluminum wire.
That should get the wire through into the passenger compartment. I use that same technique on most harnesses when I need to add a circuit.
You can us steel wire, and that will let you use a smaller gauge wire.
Good luck!
Posted by: trojanhorsepower Dec 3 2019, 06:19 PM
Got it!
Thanks Clay.
It turned out not to be as bad as I feared.
Peter
Posted by: trojanhorsepower Dec 5 2019, 07:57 PM
One more question. Is the ground point at the fuse block a bolt or a stud? I see a captive nut there near where I think the ground should be, if that is it anyone know the thread details?
Posted by: ClayPerrine Dec 6 2019, 07:30 AM
One more question. Is the ground point at the fuse block a bolt or a stud? I see a captive nut there near where I think the ground should be, if that is it anyone know the thread details?
It is a stud. It is located on the inside of the mounting bracket for the fuse box.
You should see a bunch of brown wires under the nut.
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