Make a wiring harness

I did my own wiring harness as well. not too bad at all. i have a solid electrical background, so i have a few tips for you as well, and also opinions of other comments.

first, i would draw it all out. make a diagram (unless you find one) which outlines every light and every switch it goes through to get there. then, instead of running 1 wire/circuit at a time as mentioned, you can know exactly how many wires to run and have them all labeled, running one group of wires is easier than running 4+ wires one at a time.

PLEASE make sure you have a GOOD crimper. i beg you to not use one of those trash $5 flat crimpers that strips and crimps. they are awful and the inventor of that tool should be lynched. spend some money and get a real crimper

circuit breakers are great. if you plan to use them for the larger circuits, i encourage it 100%

i personally used many connectors for a couple reasons: every light, signal, side marker has slide connectors. when i break a light on a rock, or need to replace it for another reason, i'd rather remove the light and plug in a new one rather than cut it and add butt connector again and again. also where my wires come through the firewall, i have slide connectors. this is so when i remove my tub or fenders in future for any reason, i don't have to disconnect each circuit from it's end point. some people will say every connection in a circuit is a weak link. BS! good crimps will not be a weak link. now this was just my case of using extra disconnects for dismantling/rebuilding. if not necessary for you, don't bother.

i don't reccomend cleaning up some wiring and replacing some wiring. your wiring is over 30 yrs old. GET RID OF IT ALL, the more you look, the worse it is probably. if you're gonna do it, do it right-all new

don't be afraid to get slightly heavier gauge to replace it with. nothing on mine is smaller than 14 gauge. not quite necessary, but that is my style.

plan ahead...are you going to add offroad lights? rock lights? etc? run extra circuits if you choose, you don't need to put a fuse in yet.

grounds are KEY! make sure they all have solid connections. i use a small attachment that fits into my drill. it has a small tip that fits into the screw hole and a tiny wire brush that cleans off any paint/rust/debris that could ruin a ground. also use a dab of anti-oxidation jelly on that bare spot and over the screw/connector so that it will not rust and keep that ground from corroding.

protect your wires. use plastic wire loom, zip ties to secure harness from moving around and rubbing raw. for going through holes in firewall, there is a plastic _____ (can't remember the name-we called it caterpiller) it is made to cut to size and attach to the metal. it covers the rim of the hole with plastic to prevent raw and sharp metal edge.

LABEL EVERYTHING.

sorry for the long post, but i've had 2 friends old wiring catch fire on them, and helped them both do complete rewire/harnesses from scratch in addition to my own. bad wiring jobs are scary, but good wiring jobs are a great feeling. please feel free to ask more questions. it is a good sized job, but well planned and taking your time, you will see it is not hard to tackle.

good luck.

 

Good advice from wicked4x4. I have a couple of comments to offer.

Regarding crimpers, here's a good crimper thread: http://www.garagejournal.com/forum/showthread.php?t=29216&highlight=crimper

I like to solder, but I'm good at it. You don't have to solder to get good joints, but IMO you're less likely to have a bad joint if you crimp and solder.

I've done some research and it's a fact that mechanical connectors are unreliable, compared to most electrical and electronic components. This goes double for automotive connectors, which are just good enough to get the job done. If you want lots of connectors, fine, but the factory puts in connectors to make assembly of the car easier, not for ease of service or added reliability. Consider leaving them out if you can.

I have not used the catepillar strip, but I have used grommets. Never put a wire through a bare hole in sheet metal - that's just asking for trouble.

If you check the electronics supplier's catalogs, they will have lots of cool stuff for wiring. Keystone makes a lot of connectors that are sold through Mouser Electronics. Waytek has good stuff too. Allied Electronics is another good supplier, though their minimum is high.

Re old wiring harnesses, my main problem with this is that new owners look at the rat's nest left behind by the previous owner and freak out. They think they have to rip out everything to make it right, and that's not true. Wiring harnesses can be repaired, and as long as the insulation is not falling off of the wire, it will work fine. Old wire will be oxidized, so I recommend paste flux, crimp and solder on old wiring. If you get a good solder joint, it won't matter that the rest of the wire has surface oxidation - it will still conduct 12V DC just fine.

About grounds: many, many, many problems in old car wiring are simply due to bad grounds. Cars use the body sheet metal and frame as a ground conductor, and rust, corrosion, oxidation of the connectors and the metal around the connections casues lots of trouble. Again, if you can make good contact to the base metal, it won't matter if the rest of the body or frame is rusted. All you need is a continuous path of good metal back to the battery.

hth!

 

Wow! You guys are great! I'll take all that to heart. I get the sneaking suspicion that this is going to turn into a a month long project at least haha! At least I'll never have to do it again. Do you guys have any particular advice on which connectors to use? So I gather the best course of action is to use the stock connectors with the new fuse box, new wire and add the slide connectors as per wickeds instructions. Any ideas where to get the connections needed for an alternator off a 79 waggy w/360? I saw that painless sells just the pigtails for some but beats me if it's the right kind. Don't apologize for the long posts guys, any info is good info for me as I'm about as green to jeeps as one can get.

 

like timgr said, soldering is best, can't be beat. also, heat shrink is your friend!!! and as he mentioned, i used lots of connectors, as i made mine easy to pull apart and reinstall without hacking wiring up each time. if you don't see that in the future, don't bother spending the time and money on additional connectors. you can go all out on weather-proof connectors, i didn't, even though mine sits in the rain.

if you do use any of stock harnes, just check your wires. i found oxidation a foot plus back from connections. i personally don't like oxidation-->leads to rotten and weak wires.

 

Bonding brush (Grounds)
http://www.brushresearch.com/brushes.php?c1=70

Caterpillar Grommet
http://www.surplussales.com/Rubber-Plastic/Plastic-2.html

 

Harley Davidson uses Deutsch wiring connectors. I liked that they can be taken apart and put back together and they are waterproof so I used a few of these on my Jeep. You can even switch out the pins for your particular gauge wire.

http://www.jpcycles.com/productgroup.aspx?GID=96356F24-763B-4552-A635-4F4E93E692D6

 

Hmmm, lot's of good input! I think I'm going to sort through all this info and try to get the best of all worlds here. Thanks for the help guys!

 

There is a good thread on this website: http://www.film.queensu.ca/cJ3B/Tech/WiringHarness.html

I also had a a write up on there a wiring harness I made. (This was in 1996) Here it is:

Cliff Todd: "I made my own wiring harness for about 50.00 Used crimped conectors from auto supply store. I took one wire at a time and in about four evenings after work I would take 2 to 3 hours at at time with the Jeep. Instead of taking the old harness out I would unhook the old wire and follow it the where it went and hook it up, then cut out the old wire. Kept it all running along the same path as the old harness.

"Afterward I used a plastic wire loom cover to enclose everything and used zip ties to attach it to the inside of fender or frame. Also added some inline fuses to some areas that were not protected from a previous botched job. Not a rocket science type of project. But rewarding in knowing I did it myself, and saved a wad of cash that would choke a horse in the process. Of course if you use an off the shelf wiring harness, it would be fast work and save a few hours."

 

khamil, yes and yes. the caterpillar feet grommit and the pilot brush are exactly what i was talking about. thanks for taking that extra step on what i said.

that pilot brush is one of the best damn things i have in my tool kit. i got them when i worked as an contract installer for the phone company, working on equipment racks and stuff. never knew where they got them and where to replace them. now i know...i think everyone should have one or two of them in their tool box.

 

Sorry my reply took so long. I was out of town. I bought all water proof connections from a company in Utah. Can't find the dang address no place. It was
pricey but that is what I chose. Just regular connectors from Autozone or someplace like that will work. Tell them what you are doing and if they know anything, they should be able to help you out. You can water proof with liquid electrical tape or silicone. Good luck and take your time. 1 circuit at a time.

 

I found new connectors at the local chevy dealer for my '73. Now its a matter of forcing myself to do the job.

 

For me it was a "Time vs. Money" deal.
I spent a few more bucks on a Painless kit, but it installed in an afternoon. I just put dielectric grease on the fittings for longevity and waterproofed select ones with liquid electrical tape.

 

Take a look at these for running wires through sheet metal.

They work for holes up to 3/4", standard in aircraft industry.

For larger holes, go with the caterpillar grommet already mentioned.

For connections that need to be waterproofed, use shrink tubing from a boat supply house, it has a sealant inside.

Stay away from solder joints in anything subject to a lot of vibration, go with a good quality crimped joint.

If you want to get really into wiring theory and such, here is a link to the "bible" for homebuilt aircraft wiring.

Just like using Milspec fittings and hardware, aviation wiring practices adapt well into the off road world.

 

I will run this in to the ground. if you want to do the hard stuff great! If you don't the EZ harness is the best money I have ever spent! The painfull harnesses are A LOT of money for what you get. I went the EZ way and put on GM weather pack for every thing. (www.delcity.com) all said I spent about $225 with shipping. I can unplug in sections, for instance the engine is on one plug, the hood is anther, battery anther and rear on anther. Cleans up the wires, never have a problem with water, and if i need to take hood off or harness, everything else says where it is. I priced a painfull once for what i needed (74 cj5 full kit) 400 plus. for that chunk of change it still did not offer the extras that EZ did. future expansion is very easy and some upgrades are already there (elec fan, other relays) If you build your own harness KUDOS to YOU! I have 6 years of tractor, semi, and auto wiring experience. IMO the EZ is a GREAT kit, just throw away the cheap connectors they send with it. Del city has all the high quality stuff you will need.

 

http://www.delcity.net

Thanks for all the info.