ELEC TROUBLE

[Fordguy85]

so i bought a 72 F250 to drive as a work truck an slowly restore, I knew I was going to run into problems but HOLY CRAP


where do i start, the guy before me had it rewired , the truck runs and it runs great, but it was either wired by a blind man or an idiot, the sending unit on the fuel tank has 2 wires coming off of it , on screwed into the back side of the cab for a ground and the other is just sitting on the center nut and that wire runs off behind the inner panel of the cab somewhere can find where it goes, the lights on the instrument cluster do not work at all, and the fuel gauge doesn't work any clue ??

[Nitekruizer]

The wire from the fuel sender should run up inside the rear left corner pillar, then above the driver's door and down the inside of the windshield pillar. The wire for your "Dome" light will be up there too.
First thing I would check for the dash lights would be a fuse, if you haven't already. I think it's the smallest fuse in the fusebox. If the fuse is good, then both bulbs could be burned out or the rheostat (dash dimmer control) in the Headlight switch may be burned out, but before changing the switch, it would be a good idea to check the underdash wiring for bad splices, loose connections, etc.

BTW

[Fordguy85]

seriously considering ripping all the wiring out, and redoing it all

[SDFarmKid]

seriously considering ripping all the wiring out, and redoing it all

If your considering redoing the entire wiring harness because your dash lights and fuel gauge doesn't work you must have way to much time on your hands. Like Nitekruiser said start by checking your fuses and bulbs and if everything looks good with them, get a voltage tester and a wiring diagram and start checking for voltage from the origin point outward and see if you can find the problem. If you still want to consider rewiring it i would look into some sort of kit such as painless or rebel wiring, which will allow you to upgrade to the newer style bladed fuses. Good luck

Here is the link to the wiring diagrams:http://www.fordification.com/tech/schematics_h.htm

[Fordguy85]

seriously considering ripping all the wiring out, and redoing it all

If your considering redoing the entire wiring harness because your dash lights and fuel gauge doesn't work you must have way to much time on your hands. Like Nitekruiser said start by checking your fuses and bulbs and if everything looks good with them, get a voltage tester and a wiring diagram and start checking for voltage from the origin point outward and see if you can find the problem. If you still want to consider rewiring it i would look into some sort of kit such as painless or rebel wiring, which will allow you to upgrade to the newer style bladed fuses. Good luck

Here is the link to the wiring diagrams:http://www.fordification.com/tech/schematics_h.htm

the only reason Im considering a complete rewire is because it has already been rewired and it looks to me like there were a lot of short cuts taken and there are quite a few things that just don't seem right to me, For example the battery is grounded on the intake manifold, I've only ever seen them grounded on the block or the frame, it just seems like that was the easiest way so thats what they did rather than the right way and if its like that on something like a simple ground it really makes me wonder where other short cuts were taken

[68RGR]

The ground to the intake manifold could be a problem due to the potential for additional resistance where the block meets the intake. It's just not a good idea. I'd get the right ground cable and put it where it belongs.

Regarding the dash lights - This is a long shot but, once upon a time, a fellow decided to replace the cig lighter socket in his truck. He didn't know what was what so he wound up wiring the hot wire to the correct point on the socket. BUT, he put the wire for the cig lighter lamp on the ground terminal. The original socket grounded through its contact with the dash. But, the new socket had a ground pin. So, he had two wires and they HAD to go somewhere . . .

Result - No dash lights due to a blown fuse. After blown fuse after blown fuse. A little checking revealed the problem. Once it was corrected, no more issues. Those little 2 amp fuses aren't the easiest ones to find and, these days, fuses aren't exactly a dime a dozen.

Also, take a look at this thread. It could save you some real grief down the road - http://www.fordification.com/forum/view ... =8&t=70768

Rewiring the truck isn't an easy task. Plus, if you go with one of those 'painless' harnesses, it definitely won't be easy on your wallet. It would be nice if you had a second truck so you could compare the wiring in your truck to it.

I am always curious as to the reason why a truck was "rewired" - I know there are valid reasons like increased loads that the factory wiring won't support, etc. But, in general, the wiring is the wiring and, if left alone, it will do its job just fine. I understand the impulse to yank it all out because I absolutely hate to have to go behind someone who royally messed things up. And, even after you have corrected all of the problems, you still may not have the confidence you'd like to have in the wiring.

One more example - A renter (for reasons unknown to me) removed the light fixture from the bathroom wall. When he put it back, he neglected to use any wire nuts on the connections. No tape either. No nuthin!

Result - A burned up outlet on the same circuit and, once it was replaced, a constantly tripping breaker. At least it wasn't a fuse!

[Fordguy85]

well the guy who owned it before me claimed it was his fathers, long story short his father passed away, truck sat for 5 years , he decided to start driving it and he claimed the wiring had "rotted" as he put it from sitting for so long, which seemed odd to me because my father has a 67 mustang he left sitting for 10 years and when we started working on it we replaced a few fuel lines and it fired right up , no wiring issues so i don't know why he decided to have it rewired but i do know everything minus the dash works , and the wiring to me is def not up to par

[fordman]

ajj great advisse before. the fuel wires are fine. thats the way they ae suppose to be. the dsh light wire is blue. it runs cluster lights and cig lighter night light and i think even over to the radio to suply its night light. check the fuse and the headlight switch. and bulbs too.

[Fordguy85]

i have two blue wires one is blue with a white stripe and one is blue with an orangish stripe which one is it ??

[abe]

perhaps you don't have dash lights because the rheostat on your light switch is not working. My '54 didn't have dash lights. I bought a new light switch and then I had good dash lights.