Hi, this seems like a great sight and I am in need of some guidance. We bought a 78 ranchero gt for resale. We have done a little work, but still have the electrical to go and it seems like a nightmare. The previous owner rigged the wiring and it is very difficult to tell what is what. The only thing I do know is that nothing on the dash nor the headlights works. How much would it cost for someone to fix that? How difficult is it to do on ones own? Lastly, I live in the High Desert in southern california, is there and electrical wiz out there willing to take on the task for a reasonable $$ amount. Any info would help. Al
Welcome to FTE.
The very first thing you should do is buy a service manual for that truck. Not only will it get you through the repairs, it is a little added perk on the resale.
I'm nowhere near you, but there will be another member along soon that can help you some more.
the manual is a good idea, it'll help you relate to what people suggest that you look at. like the fusible links at the starter solenoid. they have little flags molded onto them and tell the amperage. they are like an in-line fuse that burns out if need be to save the rest of the wiring. sometimes when they burn you can see it from the outside, sometimes you can't tell by looking. you can check them by testing for power by sticking the probe of a tester into the wire downstream of the fusible link. i think there may be more fusible links under the dash? not sure though, check the manual!
I did some electrical work on a 79 Ranchero. Like your situation, some guy had done a total mickey mouse (and that's a compliment) job on the electrical. I found all sorts of wire that had to connections on either side, the window wiring was reversed. Either way, I had done some minor electrical work before, but nothing like this. I found that as I got into the wiring more and more, it became easier and easier. It's just a matter of matching lines a lot of the time, and making sure the lines aren't grounded anywhere. Also, the fusible links gave me a bit of trouble. I ended up replacing the one next to the solenoid with basically a mini circuit breaker that automatically resets itself. It works the same as the fusible link, but it doesn't burn out, just closes down and opens again. I put one of those breakers right before the switch for the headlights, since the wiring in the switch kept melting as a result of the halogens.
a good/real auto parts store, or an electrical supply house. i would only replace the fusible link with a breaker of the same volt/amperage as what the fuse link was originally. the amperage is on a small "flag" attached to the wire of the fuse link.