Fuel pump grounding wire

Tiny
NOSMILEY
  • MEMBER
  • 1992 GMC SONOMA
  • 212,000 MILES
I have just replaced the electric fuel pump on my GMC 1992 Sonoma. Everything was going smoothly- tank is in position, all hoses hooked up, Ground wire attached for static electricity when filling the tank. The fuel pump and sending wire are plugged in. I can't remember the location for the grounding wire for the pump. It uses a self-tapping 1/4 inch screw- has a 13 mm head. The wire has two wires swedged into the terminal -eye that the bolt goes through. I have crawled around looking for a threaded hole mainly on the frame, or welded cross member that is close by.
The ground strap that comes from the filler tube is attached to one of the bed cross pieces(channels) that stiffen the bed. It uses a much smaller screw. The fuel pump ground isn't long enough, and has too large of hole in the eye terminal to attach there. The ground wire is the same length and made like the old one was. Feel free to address me for what I am ! I know that. I realize I can drill and tap a new hole, but was trying to avoid that.
Thank you.
Tuesday, October 8th, 2013 AT 3:13 PM

2 Replies

Tiny
CARADIODOC
  • MECHANIC
  • 33,837 POSTS
I'm having a hard time visualizing those wires, but as I recall, there is no ground wire from the tank to the body. They relied on the tank straps to make the ground for the pump with metal gas tanks. If the truck is rusty, those straps will stop providing the ground and the pump won't run. It was fairly common to drill a new hole in the flange where the top and bottom halves are welded together, outside of that weld, then attach a new ground wire. Attach the other end to the frame, not the box. We always drilled new holes in the frame and used shiny, new self-tapping screws. That way you know the threads will cut into clean, paint and rust-free metal and make a good electrical connection.
Was this
answer
helpful?
Yes
No
+1
Tuesday, October 8th, 2013 AT 11:16 PM
Tiny
NOSMILEY
  • MEMBER
  • 2 POSTS
Thanks for the help. I went back out today, determined to locate the threaded hole for the screw that the ground wires are attached with. It's on the driver's side behind one of those heavy vertical pieces that are welded to the main frame. The welded verticals are put there to serve as mounting "posts" to attach the bed. I think there are 4 total - 2 right behind the cab, on either side, and 2 right as the frame bends upward to allow the axle a space to move when it hits bumps.
These ground wires are insulated and come out of the disc that covers the hole for the fuel pump, and gage electrical stuff. One group of the wires that come through a rubber /plastic plug in the top of the disc are plugged into an existing waterproof socket, the wires going to the instrument panel and the fuel pump relay under the hood on the firewall. The other two insulated wires screw to the frame as mentioned in original post. The fuel tank has no bare copper wire grounding it to anything. Those insulated ones must serve for that too. The tank has rubber insulation strips that absorb vibration, and act (maybe not intentionally) as electrical insulators between the tank and support straps. Anyway, I'm moving along. Tomorrow, realign the truck bed with the holes in the frame, and finish.
Thanks again.
Was this
answer
helpful?
Yes
No
+1
Tuesday, October 8th, 2013 AT 11:57 PM

Please login or register to post a reply.

Sponsored links