Assistance with Restoring 73 Wiring Harness |
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Assistance with Restoring 73 Wiring Harness |
doug_b_928 |
Jan 31 2018, 03:55 PM
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#1
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Senior Member Group: Members Posts: 692 Joined: 17-January 13 From: Winnipeg Member No.: 15,382 Region Association: Canada |
My main Winter project is to 'restore' the wiring harness on my 73. I admit that of all the jobs involved in restoring this car, this is the one that creates the most anxiety in me. I took it out of it's container last winter, spread it out on the floor, and promptly proceeded to put it back in the container. But, the time has come to conquer this thing. I have 4 rolls of wire tape that cost more to ship to me than the tape itself, and I think everything I need to do the job. I have pieces of a 74 harness (which I'm aware is not the same) and have already used one of the correct connectors from it for one of the license plate light connectors. Overall, I think the harness could be a lot worse, but there are some areas where POs have made some modifications/fixes and I'm not sure what they've done and why. I'll be asking for assistance from the wiring gurus in the thread as I work my way through. I have the wiring diagram from Jeff Bowlsby's website, a multimeter, PowerProbe3, and cleaning supplies. I'm removing all the tape, inspecting, cleaning, and then installing new tape. I'm just going to clean and inspect the rubber covered sheaths as they seem to be tight around the wires and it seems unlikely that there is anything wrong underneath them (on the upside, everything that ever worked on the car during my ownership, which wasn't everything that was supposed to, still did right before I removed the harness).
Okay, so with that introduction, my first questions. Starting at the back, I've worked my way through the license plate wires, to the trunk light wires, and I'm currently looking at the fuel pump wires. My car had vapor lock, so the fuel pump was relocated to the front of the car. The mechanic just cut the wires, left the ground wire dangling, and spliced in a positive wire which he ran through the firewall (poking a hole; no grommet), under the carpet and through a hole in the front firewall, where he then spliced in the connector and grounded to a screw he added to the front firewall. Here's a pic of the wires: Because of the vapor lock issue, I'm thinking I should put my new pump in the front where the old one was (by the steering rack). I'm thinking of getting the NAPA Bosch fuel pump (N69133). From what I can tell looking at the wiring diagram, and I could be reading it wrong, the power wire goes to the 'regulator/relay plate). If it's source was at the fuse box under the dash I'd splice into the wire up there and put the original connector back on the wires in the engine bay (in case I ever wanted to put an original style in its original spot. If I'm correct about the wiring diagram, then, with my limited knowledge, I guess I have to run the power wire on the outside of the sheath (but at least it will be inside the new 914 rubber snorkel) and up to the fuel pump in the front? Is there any point in running the ground wire that way too, or would you just ground it to a screw on the car as it was before? Also, in the pic above there is a green wire that looks like it had a connector on it at one time. Does anyone know what that was for? When I look at the 73 diagram it only shows the black with red dots and the ground for the fuel pump. On the diagram it shows the, IIRC, 'fan blower motor' having a green wire. However, if that's referring to the blower motor for the heater, I think the wires and connector below were for that (note no green wire). So, to summarize, what's the best approach for the fuel pump wiring, and what is that green wire for? |
doug_b_928 |
Feb 11 2018, 12:38 PM
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#2
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Senior Member Group: Members Posts: 692 Joined: 17-January 13 From: Winnipeg Member No.: 15,382 Region Association: Canada |
Until today I haven't had any time for this project since last weekend. But I managed to finish everything in the engine compartment (including replacing the fuel pump wire with a new 12G; thanks Jeff and Brent!
The wiring in the cabin area is what scares me a bit. I'm working my way back to front. I already did the rear window defrost and the passenger seat contact and seat belt contact wiring. Here's a pic of the connector for the passenger seat contact: I can get continuity with the wires on the seat sensor when I probe from the back side of the housing, but can't when I probe from the connection/front side of the housing, so think I need to remove the plastic housing so I can clean the contacts. I don't have a spare one of these plastic housings. How does one remove the wires from this particular type of housing (doesn't look to be the same system as the spade connector housings)? |
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