47flatbed wrote:The truck has the old wires in tact, is it possible someone converted it to 12v without changing the original wiring?
I don't have much history on the truck. Ill try to take some pics of what it currently has and upload them.
Does anyone have experience on doing the 12v conversion?
Is there a wiring harness that anyone knows of that any company makes?
Rhode Island Wire makes an original wire harness - I just bought one for my brother's KB5 I am working on. His wiring is shot - bare spots, wires spliced & taped, and some corroded. Not inexpensive, but is just like factory. So far, I completed a 12volt negative ground ignition system conversion on his truck. Your, like mine, was originally a 6volt
positive ground system and may be why you fried up your wire. If you have a 12volt alternator, my guess is that it is 12 volt negative (they do make a 6volt positive ground alternator). If you have the original gauges, these will burn up using 12 volts, so you need some sort of voltage reducer unless you are installing custom gauges. So anything factory will be 6volts, positive ground.
On my conversion, I kept the factory generator but had it converted to 12volts by changing the fields and having it rebuilt. I wanted the stock look. I used a matching 30 Amp, negative ground, Voltage Regulator as the factory system is 30 Amps. Did a Pertronix 12volt, negative ground, electronic conversion on the distributor to eliminate the points & 12 volt coil with the wires swapped on the coil to go from positive ground to negative ground. Swapped the wires on the factory Amp gauge so it would read correctly for a negative ground system. Marked & disconnected all other gauge wires so as not to fry the gauges. Starter does not need any conversion or changes. Did all this to get it running on 12volts, and am now in the process of doing the re-wiring of the entire truck and swapping everything over to 12volt lights/bulbs. Also plan on installing some fuses in the system and a 12volt power block so I/my brother can add 12volt accessories in the future.
As stated, the 6volt wiring is heavier than 12volt, so there is no problem going to 12volt. Doing an upgrade as it sounds like you have, will probably take a little time and work to sort out your needs. I considered this myself, but felt it would be better to try and keep the KB5 more like stock due to its present overall condition, and I felt it simpler to replace factory wires one-for-one rather than build a wiring harness - measuring, cutting, soldering ends, shrink wrapping, testing, etc.. I am also using stock switches and the like.
If I was hot rodding or upgrading it all, then I would have used standard plastic insulated wiring or a kit, modern ignition switch, headlight switch, wiper motor/wipers, heater blower & switch, gauges, etc.. If doing this, check Speedway Motors or get their free catalog which is aimed at hot rodders and conversion type pieces. You can get some good ideas. I am using some of their catalog items myself to do a little upgrading like the wiper system, turn signal/4-way flasher unit, lights, etc..