new wiring harness

[crazywelder72]

Has anyone ever replaced the front wiring harness? i am thinking about doing it and i am curious to know how difficult is it?

 

[bigmike]

Pic #2 looks just like my harness

I'm interested in doing the same thing and have the same question.

 

[crazywelder72]

i'll keep you posted if i find anything out.

 

[Sneaker]

Just swapped mine out last year. Was a few hours of work especially if you are like me and triple check everything. I just used zip ties to re-hang the new harness to the old mounts. So I cheated a little. Really is not that hard to accomplish using the wire diagrams. If you think about it not a lot of electronics on these trucks. Inside the cab was the most difficult but I am not that flexible and small of a man to move around in these trucks well. Don't forget to have a spider harness for the gauge panel. I was surprised I had a few gauges work after I was done I thought were "toast". I bought the rear harness to do this year.

 

[Sneaker]

Oh, my harness had a circuit for a "fuel pressure switch" I had to splice it or "jumper it" so the starter would work since the M35a2 has no fuel pressure switch..

Don't quote me but it was something like 78a 78b maybe 75a 75b on the firewall of the engine compartment.

 

[Recovry4x4]

Oh, my harness had a circuit for a "fuel pressure switch" I had to splice it or "jumper it" so the starter would work since the M35a2 has no fuel pressure switch..

Don't quote me but it was something like 78a 78b maybe 75a 75b on the firewall of the engine compartment.

Sounds like a great spot to pipe in a switch.

 

[25thIDAirAssault]

Good post. Have to do front and rear in my duece. Should go a long way to fix all the electical gremlins I have. Lot easier than fooling around with my current harnesses. I will post some pics when I get going on it.

John

 

[crazywelder72]

I guess the next question is where is the best price to buy it from? I saw one place for around $245.

I would like to know more about the spider harness and the wiring diagrams. Where they in the TM's? Or is it somewhere else that it's easier to find?

 

[bigmike]

it's on the TMs.

Sneaker, I like the idea of using zip ties versus trying to re-use, re-hand all the cable hangers.

 

[crazywelder72]

Actually who knows what about the circuit breakers and any fuses. I found a circut breaker above the steering column on the firewall in the engine bay. Are there any others?

When i was checking things out the other day, the breaker was resetting after 45 seconds or so. I went to check it today and all the lights are out. I either toasted the breaker or there is a fuse I don't know about yet.

 

[Darwin T]

My M109a3 got new front and rear harness before i could get the lights to work right. it was super easy. i drove it to my mechanics and handed him the harness and when i came back it was done. i have done most of the additional wiring. he uses dielectric grease on all of the packard connections. most auto part stores carry a little can of the dielectric grease and it makes live easier.

 

[Vintage iron]

Interested in finding a good source for the M813. There is a place in RI where you can get custom wiring harnesses made. Someone I know that one made for his hot rod. The price was good and the quality was great. I will have to do some homework, but I still want to find another source

 

[crazywelder72]

Darwin, That's Cheating!!!

 

[Recovry4x4]

Wiring harness diagrams are in the -20 appendix.

 

[Darwin T]

Darwin, That's Cheating!!!

i am trying to help the american economy. i would rather take an A$$ whipping that loose my mechanic.

plus i am mechanically stupid, i can bearlly put fuel in the tires and air in the radiator.

acually i was to chicken to try. however i did do all the lights myself.

 

[steelandcanvas]

I would like to know more about the spider harness...

Here is a link to the "spider harness":
5 Wire Instrument Cluster Harness, 8376502

Actually who knows what about the circuit breakers and any fuses. I found a circut breaker above the steering column on the firewall in the engine bay. Are there any others?

The circuit breaker on the firewall protects the horn wiring, if you have more than one, the others would be for the heater, or some other accessory. The only fuse on a deuce is under the cap on the fuel tank to protect the in-tank fuel pump wiring.

 

[crazywelder72]

The spider harness is cool (and cheap). Thanks for the link.

I am dealing with the circuit breaker inside the 3 lever switch now. I have some good pics and updates in this thread.

http://www.steelsoldiers.com/deuce/15602-headlights-headlights-off-off-off-3.html

 

[Vintage iron]

Crazywelder72 let me know if you need main switch or any other parts . I have few main switches at the shop.

 

[crazywelder72]

Thanks.... but I think I'm ok for right now. The 24 volt 20 amp breaker is only 8 bucks. On the other hand, If you need me to service any like I am on this one let me know. Also don't throw away any old senders. I was able to clean up mine nicely with my ultrasonic tank. It's not big enough to do the whole thing but I put the rheostat part in and it does a killer job. Then i put the float in and lastly i put the head in. I also cleaned my fuel cap the same way.

 

[clinto]

I've done a couple now.

I pull everything out of the cab (meaning the underdash section) and let it hang on the engine side of the firewall.

Then, get under, disconnect the front (main) harness from the rear harness.

Then, slowly work it off the engine, front fenders, etc.

I can't believe you guys not using the original clamps and such. Wish my OCD would allow it


Installing is more or less the reverse. I lay it over the back of the engine, then kind of lay it where it will be going (front of the engine for coolant sensor and flame heater, front turn signals and headlights, then feed it through the firewall hole for the underdash area.

Now is the time to add any electrical accessories like 12V converters, switches for floodlights, reverse lights, etc.