Late model M170 Harness problems Packard connectors

dball · Post by **dball** » Fri Feb 21, 2014 1:35 am

Hi I am new to this site, I was a member of the old Yahoo group.
I have an 1962 M170 it is in need of a new wiring harness.
I have been reading on this site all night but have yet found anyone talking about the late USMC M38A1 or M170 harnesses. Maybe not enough of us with the need.
I have the rubber connectors on my harness on all but two senders in the engine compartment. My M170 lived in the desert and everywhere a wire enters one of those Packard connectors it has exposed bare wire.
In most cases its where the wire can vibrate and either is on a light or switch. Not sure if this is a common issue with this connector type or maybe its just the rubber wire got brittle. Anyone seen these late style harnesses in the wild anywhere? Anyone have Joe Hall make them one?

Thanks
Dave

dball · Post by **dball** » Fri Feb 21, 2014 6:53 pm

Well I guess I struck granite on that one so maybe someone can answer this.
Does the late M38A1 have rubber connectors and is it as simple as adding 20 inches to the length?
The engine compartment harness should be the same correct?
The only added wire would be for the reel light and changing the placement for the gas tank. Is it that simple?

Thanks

Post by **wesk** » Fri Feb 21, 2014 11:17 pm

Hello Dave,

Haven't seen any published Navy/Marine supply documents or factory contracts or factory BOM sheets to support harness type used on the Marine contracts after 1960. There is some evidence of Packard connector use but nothing in granite!

Physical wire damage at the junction with the connector is more common with the metal Douglas connectors but deterioration of the wire sheath is very common on both. Shedding of the deteriorated sheath happens earlier where the wire flexes a lot.

M170 harnesses show up occasionally NOS but the only ones I have seen are Douglas connectors. Some of the A1 harnesses are easy to modify to fit your needs and it is a fairly simple procedure to switch the Douglass connectors for the Packards.

The dash to rear of tub M38A1 lighting harness can be easily extended by splicing in the needed additional lengths of wire. There will be some wiring differences besides length. IE the voltage regulator to dash harness will go to the left of the firewall instead of the right.

I have several manuals that cover the A1 and M170 parts including the 1956 ORD 9 SNL G-758, 1952 ORD 7 SNL G-758, TM 9-2320-208-20P Organizational parts list and 1966 TM 9-2320-208-34P Depot level parts list. None mention the Packard connectors. I would guess there has to be some Navy or Marine pubs out there that supplemented these Army manuals.

dball · Post by **dball** » Sat Feb 22, 2014 12:59 am

Thanks Wes, One of the members here has a harness or knows of one that might work I will wait and see if that pans or I might have to pull mine and get Joe to copy it if that falls through.
This whole problem started with my headlights blowing out on a trail ride,
I replaced them and while driving home had both go again which left me scratching my head. I checked my fire extinguisher and changed the light switch which had the lockouts forced and broke at sometime and were loose and I changed the headlights for a third time and this time after dark lost a headlight. Once home on one light I started working my way front to back tracing the problem back to the dimmer switch where I found lots of bare wires. After that I got out the bright light and found that I have that issue at the trailer plug and at every switch or sending unit where the wire is bent just after coming out of the connector and with most wires missing a quarter inch of insulation.
I have all the early manuals and the Canadian ones for the M38A1 and M170 but I have yet to find a USN or USMC manual for these vehicles.
Do you think they had there own Parts supply contract with Willys?

Post by **wesk** » Sat Feb 22, 2014 1:11 am

There must be some supplemental manuals the Marines used. If you haven't noticed there are plenty of Army manuals out here and very few USAF, NAVY or Marine manuals. For some reason the annotation "Classified" and "Dispose of IAW regulation ????" seemed to be followed more closely in those three services.

I am building a new harness from scratch for my M38. I have no old harness to use for a pattern. But I don't see a major hurdles to deal with. New harnesses are rapidly approaching the $1000 mark so I don't mind a little pain and minor set backs.

skyjeep50 · Post by **skyjeep50** » Sat Feb 22, 2014 9:16 am

I replaced the harness on my M38 (Douglas connectors) because the wire insulation was basically turning to dust anywhere there was any flexing. I also bought 4 M151 blackout light housings to serve as turn signals (rubber Packard connectors) on my jeeps, 3 of the housings had supple rubber connectors but one was had a connector as hard and as brittle as glass. Check those NOS rubber parts carefully for potential deterioration. Just because they have been in storage doesn't mean they are in good condition.

Post by **wesk** » Sat Feb 22, 2014 10:47 am

The shelf life of most rubber parts is 10 to 12 years. One must always consider that when dealing with NOS items that have dates older then 12 years ago on them.

Zane · Post by **Zane** » Sun Feb 23, 2014 1:08 pm

pm sent,zane

BullRun · Post by **BullRun** » Sat Mar 08, 2014 1:00 am

The wiring harness on the '62 USMC M38A1 uses both Packard and Douglas connectors. Not sure about the '64 version or the 170. The '62 and the '64 USMC M38A1's do have some detail differences.

The more I look at my '62 the more I think it was almost hand made. There are always new details I discover that are not mentioned anywhere in literature I have found. Lots of what I think are essentially prototype parts from the Willys M151 jeep program were used to save on production costs I suspect.

There is a USMC parts manual from about '65 that mentions the unusual parts like the locking differentials etc. Portrayal Press in NJ carries a reprint.

dball · Post by **dball** » Sat Mar 08, 2014 4:55 am

Thanks for the manual lead I will contact portrayal.
My M170 temp sender is the only Douglas metal connector in the engine bay.
My air cleaner is a flat top like the M151 and some of my gauges are late types.
I took a couple pictures I will post them later today.

Thanks again

BullRun · Post by **BullRun** » Sat Mar 08, 2014 4:57 pm

If you have the flat top air cleaner that is smooth metal it is from the '62 production and also used on the very early M151 by Willys. The smooth top air cleaner lid is probably the rarest air cleaner style used on the M38A1 vehicles.

The '64 production USMC vehicles seem to use the air cleaner top with metal rings pressed into the top. This is the style very commonly seen on the M151 and the later Canadian M38A1's. I do not know if the Dutch Nekaf M38A1's used the M151 style.

I have never compared the bottom canisters to see if they are the same between the M38A1 '62 & '64 USMC and the M151 vehicles as I am thinking they are different as the oil bath air cleaner draw is rated to the engine vacuum and they would be different being different engines between the two jeeps.

The dash gauges and dash lights appear to be from the M151 jeep although I have never compared part numbers to see if they share a common origin.

Apparently my unrestored '62 got every feature and retained them over the years which it seems is very unusual as most unrestored USMC '62 and '64 USMC jeeps are missing a lot of these parts from the ones I have since found.