'79 dual tank wiring diagram

[zac]

I've got the same problems most people have with these, gauge at 3 o'clock, etc. I'm working through it OK with alot of help from earlier posts, but the '83 dual tank diagram floating around here is not the same as mine. Any help would be appreciated.

[463]

heres one thats very close

[Prong]

The 3 o'clock fuel gauge problem is lack of or a bad ground (99% of the time). Clean up the ground leads for the senders where they bolt to the inside of the framerail and see what happens.

[zac]

I actually did locate and clean up the grounds for both senders yesterday. And when I made new battery cables I massively regrounded everything (frame, body) because I've had so many grounding problems in the past. But it didn't help. The aux tank on this system is either not working or is disabled. It is an original factory installation on a K20 Camper Special, but at some point in the past Cletus did some custom work on the wiring, so this is going to be complicated. When I bought the truck a few months ago, the gauge was sort of in and out. It would bounce around somwhere near a good indication, the go to 3. Now it doesn't work at all. I printed out the diagram 463 posted above (thanks, it's pretty close), so hopefully I can work through the harness and figure it out. But one of the problems people have mentioned is that the issues could be with the valve itself. I wouldn't mind using just the left tank this winter, but I think I'm putting a 454 in this thing, so I eventually want the whole system to work. Thanks for your help.