The Stovebolt Site Forums The Shop Area The Electrical Bay Fuse box? (51 half-ton)

I'm going to have to rewire my truck and I'm looking at the wiring diagram on 12-3 in the 48-51 shop manual. Am I seeing right... only the stop light and tail light are fused? I really don't know much about electricity but isn't that odd not to have more things protected by fuses?

I assume that I can just buy a bigger fuse box and put more circuits (is that the right word?) on fuses... right? Or should I just stick to those two?

This is really starting to be fun. :/

Woody,

The folks back in those days were minimalists. I actually think there is a fuse, or if not a fuse, then a thermal overload on the headlight switch that covers the headlights.

I don't know if this headlight protection covers all the dash lights and dome light, but if you think about it, there isn't much more on these old hogs to protect...and you're working on yours, so it hasn't burnt to the ground yet.

A dealer installed radio was probably equipped with a inline fuse, as would have been a spotlight or lighted cigarette lighter. It seems prehistoric, but I don't think it's as scary as it looks.

Stuart

That is correct that only the stop and tail lights were fused. This is probably because they were located in the rear and thus were most likely to be shorted out at some point.

If you look at the design you will see that they have tried to give reasonable protection along with some safety considerations. You don't want a fuse to kill your motor in the middle of the road. There is a thermal breaker in the headlight switch that covers the headlights and some of the dash features including the dash lights. I believe that the ignition circuit is not protected but I could be wrong there. Also, the thermal breaker activates at around 45 Amps and there is plenty enough energy at well below 45 Amps to start a fire so having wiring in good condition is pretty inportant.

Thanks guys! I've always thought of electricity as some form of Voodoo but gradually that mystery is beginning to unravel... I guess old dogs can learn new tricks if they have patient teachers.

I always get a universal fuse block & hook any asses. up to it. Like heater, radio, & turn signals.

The fuse block on the 49 is larger than the 51 and it includes fuses for the headlights.

brake is fused,,heater is fused,,,dash and running lites are fused,,headlites are on CB on sw...doc

This is a comment on the above posting. The dash lights and parking lights are not fused. They are protected by the 45 Amp circuit breaker in the headlight switch. The heater is fed from the accessory terminal on the igition switch through an inline fuse.

Just one question about the ignition switch because I just read this post, but which terminal is the accessory terminal on the switch? I know there is one for things like the gas gauge and lights, and another that goes to the power source, but is that other terminal used for things like the heater? Because currently I have nothing attached to one terminal and my wiring diagram instructions had nothing in them about that terminal. I have an aftermarket turn signal kit and the heater that I will have to attach to the ignition switch.

On my original ignition switch (1951) there are three terminals. In the off position, all three are disconnected from one another. In the on postion, all three are connected together. I would think that you should bring your feed from the amp meter to one terminal and then take your switched loads from the other two. In the case of the turn signals, I powered mine from the unswitched side because I wanted the four way flashers to be available at all times. I used an inline fuse because the feed to the switch is completely unprotected.