Stripping the Wiring

[rboltz]

As we take the truck apart over the winter, the wiring was next. All the old is out and what a sight. It's amazing things worked at all. The insulation crumbled when disturbed. Pictures from yesterday after I was finished removing the last of it. Putting new back in will probably not be as easy as stripping out but at least it will be flexable.

 

[hndrsonj]

Are you going to replace it or try to fix? Replacement is better if you can afford it.

 

[rboltz]

New

Are you going to replace it or try to fix? Replacement is better if you can afford it.

99% new. There is nothing that can be re-used as far as wire goes.

 

[98taco3]

Brent Mullins has the Greek harnesses from Sid Beck when he passed away. Cost me 150 bucks for a complete harness in really good shape. Produced in the late 80s. Worth giving them a call.

 

[nattieleather]

Yep that's what happens on M serries trucks. The rubber insulation breaks down and the connectors either rust up or fuse together or both. Your smart to just replace with new.

 

[majorhitt]

Are you going to replace the harness with the same type connectors? What year is your M? I replaced all wiring. From the harness to the lights you'll need to purchase or make wire tails for each head light ETC. If you elect to fab yourself, keep note how long each tail is. If you could locate a harness it's not all that hard to install. A little assistance when laying the wire out helps, along with when it goes back in the truck. Take notes and pictures. Keep us up to date.

 

[rboltz]

Are you going to replace the harness with the same type connectors? What year is your M?

1953 Truck. About 90% will be converted to Packard connectors with those few items dificult to change remaining Douglas.

 

[1943ht]

Doing the same thing with my 53 .. just finished rebuilding the dash harness (10 guage wire) for the circuit breakers as the original wire was very crumbly .. installed a new spider harness on my gauge panel and am about finished with the dash ... ignition switch was in good shape and works as it should with a ohm meter test on each wire.. I am curious ..0f the 4 wires coming out of the switch .. I am unable to figure out what #85 does.


Am guessing that it might have provided power to the something in the ambulance model .. #12 is to distributor and matches up with the NOS harness that I found this spring ..as does #11 which runs to the circuit breakers and #27 which runs to my spider harness .. not sure what #85 does ...

 

[rboltz]

.. not sure what #85 does ...

It's sort of the "accessory" lead, but it can't take much current. #85 in some other "M" series trucks comes right off the battery lead. In the M-715, it was used for the heater but again, it came right off the battey lead to a switch.

 

[1943ht]

Thanks for the confirmation on the 85 lead .. I actually wired up two separate leads with Parker connectors off of the 2 circuit breakers that are not in current use on the truck .. one of them is going to be used for the original spotlight and stand that is being mounted on the driver side fender, going to use the other lead for my cab heater blower power source .. the heater has the resister built into the fire wall but I will have the option to use the lead for power to the resister ..

Not sure how that will work as I may have to wire that directly to my power side of my battery switch due to amperage .. believe those breakers are all in the 15 amp range but at least I have the option .. the other thought was t use that lead for an interior light that I picked up( from a 113 or Tank) .. Blue/White lens combo .. brand new and 24 volt with Parker connections .. would come in handy on my trip

Finished up my headlight dimmer swith this AM and reinstalled .. was impressed by how solid that switch is .. mounting screws came right out with a little WD application .. OHM meter test shows all the circutry to be intact on the switch .. been making a judicious use of dialectic grease on reassembly of all my wire components .. its very helpful with all the connections!

 

[Mike_L]

The circuit listing for M-series vehicles says #85 is the "low air pressure indicator light" circuit. I think the circuit number listing can be found on the Olive-Drab.com website too.

On my truck, I consider it a "free agent" for future accessories.