Electrical Help

[Tinbanger]

Hi all,

First off, thank you all for the help that this forum has provided while going through this project. I bought a '73 chevy k10 last year. It has been torn down to the frame and got a good coat of POR15. I swapped the '73 cab for a much better '83 cab, and painted the body.
It's now almost all back together, but I have hit a snag. I was driving it around the yard three weeks ago(probably the longest it had run since being back together) and the electrical system started going haywire. It blew almost every bulb in the truck and some wires started smoking.
After a lot of reading and wire tracing I believe its almost back to factory wiring (previous owner had put in a HEI and a "master" switch between the battery and alternator). I replaced the alternator, thinking it was over charging the system(it was getting 16+ volts on my meter). That didn't solve it, so I kept looking.......ended up being the battery. After that was changed the voltage dropped to 14V tops and runs great!


Now the bulbs....... I started replacing the bulbs- some started working, others didn't. My dome light(which worked before all this) will not work unless the housing is screwed into the cab. When that happens it stays on all the time!
Then the other day, my father-in-law said that one of my front parking lights and tail lights were on....The switch was off!!!
I am at a complete loss ; it's like there is a phantom 12v running through the truck passing switches and all!!!!
Sorry for the long post, i just thought the backstory would help.

Thanks for any help,
Hunter

 

[74 Shortbed]

Welcome to the site..

 

[bedwards]

Don't leave the battery hooked up until you find the problem. Sounds like you have a short in a switch or the wiring or possibly wired wrong and have by passed fuses. You didn't mention blowing any fuses. Are they in and the right size? They should have blown before you melted wiring. Also, you should only be putting out 14.5v when charging which might be a regulator problem which is built in the back of the alternator. A good battery should run from just under 12v to 13.5 when fully charged.
Your going to have to trace the wiring out and see if it is right and if you have overlooked a short and or maybe you have bypassed a switch that would keep the lights on.

 

[Tinbanger]

Don't leave the battery hooked up until you find the problem. Sounds like you have a short in a switch or the wiring or possibly wired wrong and have by passed fuses. You didn't mention blowing any fuses. Are they in and the right size? They should have blown before you melted wiring. Also, you should only be putting out 14.5v when charging which might be a regulator problem which is built in the back of the alternator. A good battery should run from just under 12v to 13.5 when fully charged.
Your going to have to trace the wiring out and see if it is right and if you have overlooked a short and or maybe you have bypassed a switch that would keep the lights on.

Battery is unhooked unless I'm workin on it. Some fuses blew, but the two wires that started getting very hot and smoking. Those were hooked up to that "master switch" between the alternator red wire and starter(battery)red wire. All the switches that control lights are new(hi/lo beam, and turn signal, have all been replaced.....albeit before this problem occurred. Main switch in the dash was replaced after.).

Thanks,
Hunter