Wiring question

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Frankie

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1989 R3500 Crew Dually. Frame off restoration in progress. Originally had a 350 TBI, will be swapping in a carb'd 454. New tanks with standard pickups. Obviously with eliminating all TBI sensor, fuel pumps etc....there are a bunch of unnecessary wires as well as the computer.

Question is...better to attempt to eliminate wires or remove all and install new fuse box and wiring? Dash will be totally torn down for various component replacement so that will help. Just trying to see what I'm getting myself into. Also prior owner has added many wires and rewired items for some reason.
 

C10MixMaster

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1989 R3500 Crew Dually. Frame off restoration in progress. Originally had a 350 TBI, will be swapping in a carb'd 454. New tanks with standard pickups. Obviously with eliminating all TBI sensor, fuel pumps etc....there are a bunch of unnecessary wires as well as the computer.

Question is...better to attempt to eliminate wires or remove all and install new fuse box and wiring? Dash will be totally torn down for various component replacement so that will help. Just trying to see what I'm getting myself into. Also prior owner has added many wires and rewired items for some reason.

personally i would rework the harness to suit my needs. Now fixing a previous owners chop job may be another story.
 

Frankie

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Besides rewiring tge main power for the windows, a mechanic had to do some rewiring when it shut off and there was zero power...no one could find out why so he ran a jumper basically from the batt.
Not sure either way will be enjoyable. Just fishing for advise.
 

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If it were me (just my opinion), I'd hit up @gmachinz and get a whole new harness. Easier than dealing with 31 year old wiring and someone else's bird nest.
 
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taggtwo

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Jabin has had my power window harness for over three months now. He must be VERY busy. Sure would like to have it back.
 

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If it were me (just my opinion), I'd hit up @gmachinz and get a whole new harness. Easier than dealing with 31 year old wiring and someone else's bird nest.
I am of the firm belief that if you dont know what you are doing,and are especially unwilling/unable to learn, you should just not touch it.
I had to frankenstein my tail lamp wiring after my grandpa.... instead of using a t connector for trailer wiring, he cut both plugs and butt spliced the main harness to eachother, then shortly UP the line to the bulkhead used wire taps for the trailer plug and then by the cab used splices for his auxillary headache rack wiring.....he was a smart man but he was NOT an electrician or should have been touching automotive wiring.

Best is, he probably thought he nailed it the whole way.


Ahhhh, grandpa.
 

Frankie

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I am of the firm belief that if you dont know what you are doing,and are especially unwilling/unable to learn, you should just not touch it.

I agree with this statement. Not sure what the previous owners specialty was but it was not wiring of any sort. I can do the wiring, slowly, but it would be done right. Problem is I'm not sure I want too. Luckily this year came with the carb swap we are doing so I know it shouldn't be too bad. I do have all the schematics. Just don't need the horn going off when you turn the wipers on. LOL
 

Matt69olds

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If your idea of correctly wiring anything includes Scotch-Loc, scotch-loc style wire taps, uninsulated butt connectors, or you don’t own or know how to use a test light, multimeter, or wiring diagram, close the hood, toolbox, whatever, and find someone who does. Or be willing to take the needed time to learn how to do it the correct way.


I hate finding cheap butt connectors, wire nuts, or cheap electrical tape in any car/truck. Why anyone in their right mind would buy that cheap harbour freight electrical tape is beyond me. That stuff won’t stick to anything!
 

Frankie

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I agree. We knew we had some electrical issues as the pumps would intermittently not work. Quick fix was adding a ground wire directly to the pump wiring. Also the wiring going to the main switch was ran from the batt via a nice red wire. Had the same wiring for the trailer brakes as well as something that was hooked up at some point, but wires where just cut and left. Beyond me how I drove this for 10 years with no real issues. Oh and the current fuse box is....well....a cluster to say the least. Luckily not having to worry about computer, fuel pumps, and sensor will make it easier. If I can find someone local to do it, that is the route I will go. I can use the necessary tools to do the job but honestly I really don't want too and I can't seem to locate an aftermarket or OEM harness. I can get one for the rear and for the headlights which does help some but not sure of the year I should be looking for. '86-'89, mostly '87 parts, a true Frankenstein from the factory.
 

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If your idea of correctly wiring anything includes Scotch-Loc, scotch-loc style wire taps, uninsulated butt connectors, or you don’t own or know how to use a test light, multimeter, or wiring diagram, close the hood, toolbox, whatever, and find someone who does. Or be willing to take the needed time to learn how to do it the correct way.


I hate finding cheap butt connectors, wire nuts, or cheap electrical tape in any car/truck. Why anyone in their right mind would buy that cheap harbour freight electrical tape is beyond me. That stuff won’t stick to anything!
i can show you a tail light harness from a different person if you want.. hehehe
 

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I've rewired 4N cars using 4-5 old harnesses to make one good one - making some added relays to improve things along the way. I bought a whole new harness from Painless - was faster and cheaper than waiting for a response I never got either. Everything's labeled and sub-harnesses like PW, etc. - those are available if you want to buy them or the diagrams are en mass to make one.
 

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That’s ok, I have seen plenty of hack wiring jobs. After awhile, they all begin to look the same.

I did not mean to insult anyone’s lack of knowledge, or desire to learn. Most major electrical issues are due to improper repair or modifications. The cheap butt connectors are not sealed, they will begin to corrode as soon as they are put into service. I’m sure anyone who had worked with these trucks for long has seen screwed up tail light harnesses from trailer connectors. My favorite is multiple crimp butt connectors, in the same wire. Usually with some obviously much older than others. If you have a wire with multiple “repairs”, cut that **** out and make one PROPER wire repair.

I wish aftermarket parts suppliers would raise the price of their stuff a few pennies and include good heat shrink crimp connectors, or lower the price a few cents and not bother including the cheap crap in the first place.
 

Frankie

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Sad to say I created one of the aforementioned wiring umm....we will call it a unique fix. Wiper control in turn signal broke so no wipers. Ran a hot wire to the correct wiper motor and to a toggle switch. At some point switch fell off so wires where just pinched together if it was raining. Was seldom driven and I knew it was going to be torn down anyway. Yes I have rednecked my share of just about everything on a vehicle. But my son is restoring this and not taking any shortcuts. Wants car show quality as that is about all it will be used for.
 

AuroraGirl

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That’s ok, I have seen plenty of hack wiring jobs. After awhile, they all begin to look the same.

I did not mean to insult anyone’s lack of knowledge, or desire to learn. Most major electrical issues are due to improper repair or modifications. The cheap butt connectors are not sealed, they will begin to corrode as soon as they are put into service. I’m sure anyone who had worked with these trucks for long has seen screwed up tail light harnesses from trailer connectors. My favorite is multiple crimp butt connectors, in the same wire. Usually with some obviously much older than others. If you have a wire with multiple “repairs”, cut that **** out and make one PROPER wire repair.

I wish aftermarket parts suppliers would raise the price of their stuff a few pennies and include good heat shrink crimp connectors, or lower the price a few cents and not bother including the cheap crap in the first place.
I had 3. 3 butt connectors in short distance to eachother. then where the trailer wiring spliced in, t taps, then one wire had a wire nut wrapped in oogles of electrical tape.

Of course, original connector is no where to be found in this case.
 

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