Wiring Harness journal

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Dleslie212

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Hey all. I'm starting on my complete rewire as of yesterday. I thought it'd be interesting to share progress and keep a little journal, so here's the first entry.

77 K10 that was bought a few years back and I've been slowly fixing up. For Christmas I asked for a Painless kit, and I've been sitting on it since trying to psyc myself up enough to get started. I took these pictures last week, and started pulling the old harness out yesterday. As of now, I have most of the driver's side harness disconnected. Hoping to get the rest of the engine bay finished up tomorrow

The wiring has been a nightmare for me since the day i bought it. It miraculously hasn't caused any problems yet, but I've been waiting for the day I'd need to trace out a wire to figure out a problem. A previous owner has hacked the harness to hell, complete with wire nuts, twisted together and taped connections, and even wires that just don't go anywhere. I'm hoping to have this done within a few months - I only get an hour or two on weekend days to work on this.
 

rusted nuts

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Good luck. Will be worth it.
 

Dleslie212

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Dleslie212

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5.7L 350
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Doppleganger

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At least your wiring is different colors. What started my complete tear down was my truck stalled on a major street. Could not get it to start (carb was garbage). When I flipped on the hazards....there was none. So I was waving people over - half of them telling me I was #1. I finally get it started and onto a side street where I get it running good enough to get home. Only gauge that worked was the speedo. So I went under the dash to see just WTF was cobbled and found a ball of solid core red wire the size of a volleyball on the left side. From that mess, a clear wire (speaker? lamp cord?) was going to the right side towards the blower......on a heater core that was disconnected and bypassed. My guess was he was installing a lamp next to the microwave he had also planned for the truck. So on that revelation, I dropped the insurance and started taking things apart. After removing everything that was wrong, this is what I had left. Needless to say, the hazards will work. lmao

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RanchWelder

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It's OK, mang...
 

Juggernaut

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Make sure to keep ALL of your old wire harness. You will find Painless leaves out several harness connectors that are not being reproduced. You will also need any harness that has been plugged into the OEM fuse block. Hopefully they are all in good shape
 

Doppleganger

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^^^ What he said x1000.

You can buy the connectors for the main block at NAPA (have to sell your truck to pay for them there) or at Rockauto for fairly cheap.

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Dleslie212

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^^^ What he said x1000.

You can buy the connectors for the main block at NAPA (have to sell your truck to pay for them there) or at Rockauto for fairly cheap.

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Thanks for the info. I haven't removed everything yet but I'll be posting more soon
 

Dleslie212

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K10
Engine Size
5.7L 350
I spend a few hours and finished up on removing almost 100% of the engine bay harness today. I got the wiring harness for my Pro Flo system disconnected and laid aside. I have the rear harness that has the wiring for the tail lights and fuel pumps, and the cab and AC harness left before I can start on the new harness. Taking previous posters advice and not throwing anything out, instead it's all going in a cardboard box that I plan on burning when I'm all done :/

I tried to not cut any wires but it was impossible. I had to cut quite a few, hoping that won't bite me in the ass later. I'm including a few pics of here of some of the fuckier things I found while removing
 

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