Fuse question (what is this for? Empty on a schematic)

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Bextreme04

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And yes, I do have the 30a removed, just have to go to the parts store today to get a 10a because of course....I have a 5, 15, 20 and a 25 in my drawer. Lol.
They sell auto resetting CB that fit in a fuse spot. I would get one of those instead of another fuse. They are the two silver rectangular ones you already have in your fuse box.

This reminds me of a truck that I worked on when I was a contractor in Afghanistan for the Marines. They had a truck that was parked for months waiting on an entire chassis harness to come in, because the headlights didn't work. The marines had hard wired a 10 gauge wire from the battery box, to a loose open switch zip-tied to a hole in the dash, then out directly to the headlights(which they had cut the connector off of and then open butt-crimped the wires too). They finally parked the truck because when they were driving across the desert at night the switch would touch the metal dash and spark all over the place. They had no breakers or fuses anywhere.

I ended up ripping all of that out, then putting new headlights in so that I could actually plug them into the harness, then troubleshooting why the lights didn't work. It turned out to be a bad resettable circuit breaker(they use them instead of fuses on the oshkosh military trucks). So they had a $250k military truck parked in the motorpool for months, then almost burned it to the ground, then ordered another $6k wiring harness for it... all because they couldn't properly isolate the real fault in the first place. It would have only cost them a $2 resettable breaker and 5 minutes of troubleshooting with a multimeter the first time.

All that to say... don't go too far down the rabbit hole here. Get the wiring schematics for your specific truck and trace the wiring to find where the original problem occurred. Don't think that you need to be stuck with whatever BS the original owner saddled you with.
 

CalSgt

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If you have the time and money, it isn't a bad idea. I've thought about doing it too, but I'm replacing the entire engine harness anyways when I do my swap.. hopefully next month. My 67 Riviera is a basketcase of wiring and has the old glass fuses, so I decided to just get a whole new painless kit. It's a nice quality kit and was about $500 for the entire car harness kit.

Have you looked at the Ron Francis express kits or had any experience with their product? That's the one I was considering for my build until I laid out the factory wiring and it was in such good condition.
 

ChuckN

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They sell auto resetting CB that fit in a fuse spot. I would get one of those instead of another fuse. They are the two silver rectangular ones you already have in your fuse box.

This reminds me of a truck that I worked on when I was a contractor in Afghanistan for the Marines. They had a truck that was parked for months waiting on an entire chassis harness to come in, because the headlights didn't work. The marines had hard wired a 10 gauge wire from the battery box, to a loose open switch zip-tied to a hole in the dash, then out directly to the headlights(which they had cut the connector off of and then open butt-crimped the wires too). They finally parked the truck because when they were driving across the desert at night the switch would touch the metal dash and spark all over the place. They had no breakers or fuses anywhere.

I ended up ripping all of that out, then putting new headlights in so that I could actually plug them into the harness, then troubleshooting why the lights didn't work. It turned out to be a bad resettable circuit breaker(they use them instead of fuses on the oshkosh military trucks). So they had a $250k military truck parked in the motorpool for months, then almost burned it to the ground, then ordered another $6k wiring harness for it... all because they couldn't properly isolate the real fault in the first place. It would have only cost them a $2 resettable breaker and 5 minutes of troubleshooting with a multimeter the first time.

All that to say... don't go too far down the rabbit hole here. Get the wiring schematics for your specific truck and trace the wiring to find where the original problem occurred. Don't think that you need to be stuck with whatever BS the original owner saddled you with.
Thanks! Great story by the way. I will start looking at the wiring, had to be something simple really. I did download the wiring schematics for my truck, but I’m going to have to relearn how to read them. It gets pretty mind-boggling, looking at all the different parts of the schematic.

And thanks for the tip on the resettable fuses. Good idea!
 

ChuckN

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Have you looked at the Ron Francis express kits or had any experience with their product? That's the one I was considering for my build until I laid out the factory wiring and it was in such good condition.
The only thing Ron Francis I’ve used was a ground harness for our old ‘54 3100. The frame was a little bit rusty, so I wanted to make sure I had good grounds. Other than that, haven’t use their stuff. Right now I’m looking at a possible Painless wiring kit, or a American Autowire kit. Seems like most people have a preference for one or the other.

Last time I bought a real generic 12 circuit harness for my old 3100. But this time I’m going to go plug and play and just spend the cash so I don’t have to spend so much time (when I do decide to purchase).
 

CalSgt

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The only thing Ron Francis I’ve used was a ground harness for our old ‘54 3100. The frame was a little bit rusty, so I wanted to make sure I had good grounds. Other than that, haven’t use their stuff. Right now I’m looking at a possible Painless wiring kit, or a American Autowire kit. Seems like most people have a preference for one or the other.

Last time I bought a real generic 12 circuit harness for my old 3100. But this time I’m going to go plug and play and just spend the cash so I don’t have to spend so much time (when I do decide to purchase).

I haven't used any of the major brand rewire kits, just shopped them for a few months when I was considering a rewire. The painless and American Auto Wire stuff looks better (at the fuse panel) and kinda almost stock for some of the kits.

Seems like the Ron Francis stuff really pays for doing custom jobs, they have you designate what style column, ignition switch, dimmer switch, turn switch, alternator, EFI/carb, stock or aftermarket gauges, Etc. on the order form. They should be able to plug and play in something that has been totally altered from stock.
 

Terry Wilkerson

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Have you looked at the Ron Francis express kits or had any experience with their product? That's the one I was considering for my build until I laid out the factory wiring and it was in such good condition.
I used Ron Francis on my shoebox ford. It is good quality and their customer service is outstanding.
It a bit more expensive than some.
One more thing that differentiates it from others is the fuse block has no wires attached to it. That allows you to work from the fuse block to the accessory or from the accessory back to the fuse block. Which ever is easier for that circuit.
 

Ricko1966

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What wire did you ground out? Anyways don't connect it to sender,first check resistance to ground on what you suspect is the correct sender wire,open? Try grounding the wire with a new fuse. Does your gauge work now? I'm thinking someone may have hooked an electric choke wire to temp sender. IMHO one of the 20 amps you have will be fine.
 
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ChuckN

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What wire did you ground out? Anyways don't connect it to sender,first check resistance to ground on what you suspect is the correct sender wire,open? Try grounding the wire with a new fuse. Does your gauge work now? I'm thinking someone may have hooked an electric choke wire to temp sender. IMHO one of the 20 amps you have will be fine.
I think I found it. Wire looked orange at first, but it was just weathered- as I peeled back the tape, it turned color to pink/black.

So I looked at the wiring diagram and it looks like he may have hooked up the idle stop solenoid wire to the temp sensor on accident. Not completely sure as I haven’t trace the wire all the way back to the fuse panel but it’s the only black/pink wire that I can see on the diagram.

So the pink/black wire was hooked up to the sensor, and that’s the one I thought was the sensor wire. So I grounded that one out and that blew the fuse.

The gauge is still not working, even though I seem to have found the right temperature sensor, dark green wire; it doesn’t have any power going to it at all. I checked with both a test light and a voltmeter.
 

Ricko1966

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Ground it see if the gauge pegs.
 

ChuckN

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@Ricko1966 You may remember my other thread so some of this will sound familiar. Stay with me. The pink wire going to the temp sensor is now capped and tossed aside.



dark green wire (temp sensor wire) grounded only moves the temp needle to the 10 o clock position off of cold. But here's where things get weird. If I connect the electric choke ground wire (Edelbrock) to the carb grounding screw, everything does haywire. The Temp gauge shoots to hot and the test light that is connecting the green wire to ground (on the intake manifold) goes dark. Then the temp gauge stays that way (on Hot) until I disconnect the electric choke ground wire and manually take the test light and re-ground the electric choke to the negative battery cable. Then, the temp gauge will reset back to cold. I have no idea what's going on.
 

Ricko1966

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What color wire is going to the choke? Check it against a schematic. This truck was a 6 and p.o. swapped to V8 who knows what wires he's connected where,and what's back feeding what get a schematic for your 6 cyl. Truck locate factory wires by color and run them to the correct locations,I think this is the problem.
 

ChuckN

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What color wire is going to the choke? Check it against a schematic. This truck was a 6 and p.o. swapped to V8 who knows what wires he's connected where,and what's back feeding what get a schematic for your 6 cyl. Truck locate factory wires by color and run them to the correct locations,I think this is the problem.
You're speaking my language. I think he probably relied on memory to get it back together but likely got some wires crossed. The wire to the choke is black but could be spliced in, I'll have to peel back some more loom later tonight and do some lookin'. According to the diagram, I'd imagine it would be referenced as "choke heater".
 

Matt69olds

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The blank spot is the power feed for power windows. It has a plug that snaps into the empty cavity, the power window feed connects to that. There is a 30 amp circuit breaker that bridges the empty spot. If something is plugged into the left cavity (where the circuit breaker would go) whatever is connected isn’t fused by anything other than a fusible link.
 

Matt69olds

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Found this pic online, you can see the pink pigtail that the power windows would plug into. The circuit breaker bridges the gap. If your truck doesn’t have power windows, they will be a blank spot where the jumper snaps in
 

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