Is this a mistake or is it "Painless"

[Hedgehog]

Amongst other major and minor issues with my CJ (the major issues are being taken care of) a lurking issue has raised it's very ugly head. ~40 year old wiring. First off be aware in '75 CJ wiring was in transition. Pre '75's didn't have a fuse box. The '75 does. '76 and newer CJ's have a GM style steering column with in the column ignition and turn signals. The '75 doesn't. When I got the CJ it had issues, the fuse box had experienced a short in some circuits I.E. parts are all melty. Some wires are patched, others are fried (under the hood). Lately all the lights have started to flash and the switch is hot. I've dug and patched and fixed enough. It's time for a new wiring harness.

Naturally the differences between '74,'75 and '76 CJ's are raising their ugly heads. After much dithering a Painless Wiring Harness for '75-86 is on it's way to my little house. Expensive is a word that doesn't exactly cover it. The '74 harness would have worked, but the stock style fuse box would have been replaced with a Painless work around. The '75-'86 harness has the proper fuse box, but I'll have to figure out how to wire the ignition switch and turn signals. My DUI ignition and single wire alternator are far different from stock so wiring the ignition will be interesting but familiar work. I hate wiring turn signals, there is an electrical magician in there that goes beyond my understanding. Other than those issues this seems very do-able or am I fooling myself.

Have you '75 owners faced this very same problem, if you have how did you deal with them? If you've worked with Painless Wiring Harnesses feel free to chime in, any and all information will be helpful.

 

[Lumpy Grits]

Run your head-light circuit through a relay.
http://www.jeepfan.com/projects/brighten-your-lights-installing-headlight-relays/
That takes the 'load' off of the switch. Same for you heater's blower and wipers.
Do you have a dedicated ground(GND)from your dash panel to the NEG(-)of your battery? You should--
LG

 

[007]

1. I know less about wiring than many/most.

2. I'd use a relay everywhere I could.

3. I installed a ground terminal block under hood and under bed, if I were you I'd do that and put one under dash too. Good ones are inexpensive.

4. I'd ground everything I could to these blocks - pretend you have a fiberglass tub and frame and wire accordingly.

5. The project is going to $uck, but when you're done you'll be thrilled with the finished product.

 

[Hedgehog]

Yes, yes I know about proper grounding and relays. Even though the jeep has run for ~40 years without all these desperately needed relays. I know this is running against the current trend I'm not completely sold on the real need. Honestly adding relays everywhere seems to double the needed wiring. Aren't relays meant to reduce the stress on your switches? It seems like using properly sized switches would be the real answer rather than running two wires where one would do the job nicely. With that being said, running a relay for the head lights does make sense.

It is my intention to strip out every darned wire in the jeep and replace it. That includes cleaning all grounding surfaces. So, yes proper grounding is important and that leads me to wondering, should I run an extra ground wire or two in the wire loom to make sure the ground wire doesn't need another ground wire just to make sure the ground is properly grounded to the ground (battery ground that is).

 

[007]

My battery cables have little 10 gauge wire connectors built into them. I ran from one of those to my firewall ground distribution block. Then I ran a dedicated wire from that one to the one in the rear.


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[Hedgehog]

Grounding and relays are sort of general "good to do" items that I will use. I guess I'm looking for specifics like are the wire colors in a Painless wire loom consistent with the colors AMC used in our CJ's, especially when it comes to lighting. I.E. if AMC used light green and a black strip for the left tail light turn signal, will the colors be the same?

 

[jdcaples]

+1 on all 007's points. I got mine from Blue Sea Systems:

Something like this, but I can't remember what I installed.

https://www.bluesea.com/products/2303/Common_150A_BusBar_-_Four_1_4in-20_Studs

I also used 1/0 and 2/0 welding cable for battery and alternator output.

Lumpy Grits, obviously, is correct, but I think you want to refresh your CJ's electrical.

Having said that, I probably wouldn't buy a Painless Performance harness again myself just because I live in a rainy climate and there are more moisture resistant products out there which I found out about after arching my back and cramping my hands for too many hours. I also suck at wiring in general, so when all was said and done, it isn't perfect, but it's better than the PO mess I was driving.

Since you live in an arid climate, the Painless harness might be a good choice. Read the manual for the harness to make sure you buy something advertised as suitable.

I thought their product was well-thought out; it's nice the colors (are supposed to) match factory. Each individual wire will have tiny little writing on which, with reading glasses, is legible to my 51 year old eyes, but not without reading glasses.

Take your time. I found that if I tried more than one or two circuits in a row, fatigue made me make mistakes. For instance, I got greedy once and right now my fuel gauge is being powered by a jumper from the radio (ignition-switched) power wire. I'm sure the fuel gauge power wire is in that mess, (safely terminated because I remember making sure it was secured with a wire nut and taped for good measure) but I'm not digging it out any time soon. Another time I got greedy and couldn't manage to run my voltage sense wire to something further than the alternator. Result: my alternator congratulates itself for providing proper voltage at idle, when the rest of the Jeep gets a little under 12 volts at 650 RPMs. I still haven't managed to "fix" that.

I'm bitter about how difficult it was for me to physically complete.... it wasn't mentally hard, it was just back breaking, muscle cramping work. It also claimed the life of my ancient wire strippers, so now I have wire strippers that I probably won't use again in the next 10 years.... because I HATE WIRE WORK!!!!

Besides, how will I be properly vilified by the next owner if I don't leave a little headache or two behind

-Jon

PS: I don't have a garage. I have gravel driveway. It rains a lot here. I recommend removing the top, the seats, the steering wheel, supporting the dash on both sides and maybe any roll over equipment just so you're not bending your body around anything.

Direct access will make it a lot simpler. The seats and the top and the steering wheel were frustrating, maddening obstacles that made me day dream about taking a SawzAll (reciprocating saw) to them. On the plus side, I am happy about the curly loops I added under the hood so vibrations aren't so bad on the connectors.

 

[Lumpy Grits]

By going to the relay type circuit-Your headlight switch no longer carries the full amperage load of the entire headlight circuit as it now does and that's why the switch gets hot. With the relay installed, the switch is now only the 'trigger' for the relay to energize the circuit.
Having dealt with Painless wire looms in the past. I learned that they are anydangthing but painless.
LG

 

[Lumpy Grits]

Yes, yes I know about proper grounding and relays. Even though the jeep has run for ~40 years without all these desperately needed relays. I know this is running against the current trend I'm not completely sold on the real need. Honestly adding relays everywhere seems to double the needed wiring. Aren't relays meant to reduce the stress on your switches? It seems like using properly sized switches would be the real answer rather than running two wires where one would do the job nicely. With that being said, running a relay for the head lights does make sense.

It is my intention to strip out every darned wire in the jeep and replace it. That includes cleaning all grounding surfaces. So, yes proper grounding is important and that leads me to wondering, should I run an extra ground wire or two in the wire loom to make sure the ground wire doesn't need another ground wire just to make sure the ground is properly grounded to the ground (battery ground that is).

Remember this-Our Jeeps were never built to last this long.
Also, in '75 relays weren't even around for automotive use.
LG

 

[Peanut Butter]

Before you get started HH, I would buy one of these. I love mine. I doubt that I could have rebuilt my harness without it. colorwiringdiagrams.com

 

[Neuner]

I guess I'm looking for specifics like are the wire colors in a Painless wire loom consistent with the colors AMC used in our CJ's, especially when it comes to lighting. I.E. if AMC used light green and a black strip for the left tail light turn signal, will the colors be the same?

Wow, they can't get off of the relay thing, huh?

Have you ordered the painless harness already? I haven't read of anyone saying it was an easy swap. I'm assuming it's because they don't use the same colors. If they don't then they should have at least a wiring chart and corresponding connections provided with the instructions.

Not sure if this would help or not but when I did my engine swap, I had to tie old AMC wiring into new Chrysler wiring with various colors and traces. Before clipping the wires on either the old or new harness, I traced them out and put permanent tabs on the ends of the wires and wrote the corresponding color code on the label. If there was room, I abbreviated what it was for. This was a huge benefit and they are still on there, wrapped up in the loom. The only two that were incorrect were the ones for the CPS Sensor because all three wires were a solid black. It might help to label the painless wires if they don't already have it on there.

 

[Lumpy Grits]

"Wow, they can't get off of the relay thing, huh?"

They work-that's all
You reduce load and voltage loss(brighter lights)by not run'n the full current load through the whole circuit. Plus, switches will last longer due to reduced current at the switch contacts.

LG

 

[Hedgehog]

I haven't ordered the harness yet. I thought I did, but my company shut off JAVA and I can't order on a secure line without it. So, is there something better out there for a rewiring job?

One thing is for sure, I've had enough of this old, patched, cooked until brittle, faulty wiring. I believe changing out the 1/2 melted fuse block will help immensely.

Neuner - Yes the relay thing along with the ground thing is important to many who have dealt with wiring issues. I understand it. The constant warnings are good for the new guys on the board. While I've read the same thing about 100 times it's there might be someone new that has never seen that advice before.

 

[Hedgehog]

So, lumpy - to do this right I should run a relay to all my lights ... each separate marker light, turn signal, head light, brake light, back up light, running light, gauge light..... yes I'm picking on you a little, but in fun not aggressive rebellion.

 

[Lumpy Grits]

Just put the relay in the driver's seat........

LG

 

[jdcaples]

I think EZ makes a wiring harness that someone used in a Jeep. I'd call to see if they match to factory color scheme, or if they're universal.

Home

Summit Racing has a lot of wiring harnesses available, but their product finding tool only shows Painless Performance kits are compatible with a '75 CJ5 .

-Jon

 

[Neuner]

I think you should have relays for your relays.

Now that I think of it, just to be safe, you might also want to relay that relay.

 

[jdcaples]

I forgot about Centech

Early CJ Wiring Kit

-Jon

 

[Hedgehog]

Okay, after looking at all the options, and I really looked I went with the Painless wiring loom from Summit. I found this one thing to be disappointing, the website shows that customizing is available, NOT!

All n all knowing the wiring modifications that have been done there shouldn't be any real problems working with this kit. Now to find relays sold in bulk. I'm at needing 30 and counting. Since each relay will need a fuse that's 30 weather proof fuse blocks. Man this will be expensive. Lets see, I'll need to run hot wires to make the switched hot wire hot that another ..........

 

[jdcaples]

The one thing about the Painless harness that drove me bonkers: no 4wd indicator lamp wire. I must have looked for it for hours. Turns out the kit I bought doesn't include one.

I've yet to DIY it. Doubt I ever will.

-Jon