Posted by Sherman in Idaho [98.225.32.22] on Saturday, March 09, 2013 at 12:20:18 :
In Reply to: Wire melted in like 5 seconds! posted by Sterling From TX [99.98.76.231] on Friday, March 08, 2013 at 02:28:50 :
If I understand it correctly, the wire from the switch to the solenoid melted. Nothing wrong inside the switch could cause that. The first obvious problem is you did not have a fuse in the circuit. Everything except the fat wire to the starter motor needs a fuse. You can get fancy and have a nice fuse block with lots of different fuses for different circuits, or you can just have one in-line fuse for the whole system (not recommended) but it needs to have a fuse sufficient to prevent melted wires.
My guess, and this is just a guess, is that you connected the downstream end of the wire to the starter solenoid to the wrong place. You'd mentioned earlier that there were two fat terminals and two small ones on your starter. I'd never seen one like that so didn't have anything to say about it. Perhaps one is upstream of the solenoid and one is downstream of it, or perhaps one is the ballast resistor bypass position like on a Ford starter relay. I wouldn't want to guess from here what your setup is supposed to be or what you did wrong. It's even possible that there is something different between the two switches that made the first case tolerant of the is-wiring, but in the second case, it wasn't. For example, you could have miswired the starter and so that the wire was "live" when the truck is running, and the first switch might have left that wire open while the second one grounded it.
I really think you need to find a friend who's comfortable with electricity to sort all this out for you. It's pretty easy in person, but next to impossible to figure out or describe long-distance.