Question: MBT\Bantam - Understanding Wiring Part Numbers

[Chance]

My trailer does not have any of the original wiring. I am trying to understand what wiring components (part numbers) are needed. I have the following two manuals, as listed below, that I am working from.

TM-10-1281
September 30, 1942
Contains:
A-6338 Trailer wiring harness (4 wires in braided loom)
A-6339 Connector to blackout tail light cable - Left side
A-6340 Connector to blackout tail light cable - Right side

SNL G-529
5 July 1945
Contains:
A-6339
A-6340


1. What is A-6338? Does part number A-6338 connect the left and right tail lights? (I know that A-6339 and A-6340 go from the black out switch to each tail light.)

2. A-6338, as a part number, does not appear in the SNL G-529, as referenced above:
a. Is part number WEB-3695, PLUG, tail light jumper cable, assembly, in the above SNL G-529 an alternate part number for A-6338?
b. Or was part A-6338 eliminated by the time SNL G-529, 5 July 1945?
c. Is this a Willys vs Bantam issue?

3. Does anyone have a trailer layout of the wiring by part numbers? (That would be helpful to me to visualize what is what and where it goes.) I found one, but it doesn't reference part no. A-6338, but it does show wiring between the tail lights (hence my assumption above).

4. Is there a GOOD manual that I can reference, or a better one I should say, that will help me during my restoration?

[Ben Hovis]

Chance,
Here is the diagram for wiring that I used on my 1943 Bantam T3.

Trailer_wringBantam T 3.jpg (68.89 KiB) Viewed 1633 times

I did my own harness which is very easy.

boswitch3.JPG (39.04 KiB) Viewed 1633 times

harness3.JPG (26.69 KiB) Viewed 1633 times

More pictures on my website in trailer section. http://www.jarheadjeep.com
Ben

[Chance]

Thanks Ben this is very helpful! I've pointed a few others to your site too.

Still, any ideas on the part numbers cited? (Original post.)

[Ben Hovis]

Chance,
The manual I used is TM 10-1281. Your numbers are the Willys MBT numbers. Both Bantam and Willys part numbers are listed. If you want a repo made G 509 wire harness ready to go I think Ron F. has them. You will also need the main plugs that go to your jeep to trailer. Check with Ron F. ( https://www.vintagejeeps.com/c-24-24-trailers.aspx ) as not sure if he has them ( if he doesn't I may know who could have the plug) or you can find them on ebay too.
The wire connectors are on the wiring diagram that are posted earlier.
As I mentioned they are really easy to make ( I used 12 gauge wire) and then just put the lines in the wiring covers in the pictures Just follow the color coded wires and get connectors from Ron F. NAPA Parts and many other auto parts stores sells wiring covers too. See pictures.
Ron sells the clips too:

Grommetsclips.jpg (85.93 KiB) Viewed 1586 times

You should call RonF. as he may additional parts you will need.
Hope this helps,
Ben

[Chance]

Thanks again, Ben. This helps quite a bit.

With regard to identifying the wiring part numbers and their placement on the trailer maybe this sketch will help with my questions:



1. What is A-6338? Does part number A-6338 connect the left and right tail lights? (I know that A-6339 and A-6340 go from the black out switch to each tail light.)

2. A-6338, as a part number, does not appear in the SNL G-529, as referenced above:
a. Is part number WEB-3695, PLUG, tail light jumper cable, assembly, in the above SNL G-529 an alternate part number for A-6338?
b. Or was part A-6338 eliminated by the time SNL G-529, 5 July 1945?
c. Is this a Willys vs Bantam issue?

3. Does anyone have a trailer layout of the wiring by part numbers?

[Ben Hovis]

Chance,
Do you have the G529 manual? You can down load it from Jon's site below and read the electrical section:
http://jeepdraw.com/TRAILER_TM.html this manual is great to work out your plan.
If you go to the wiring you can see how the wiring goes. You can buy the wiring harness all ready done. You will have to buy the rest of the parts in the manual from different sources. After you check out the manual and you have any questions we can see what you want to do IE make your own wiring or purchase a harness.
Ben

[Chance]

Ben, thanks. Yes I've visited and it is a great resource!

Do you know what part number A-6338 is?

1. What is A-6338? Does part number A-6338 connect the left and right tail lights? (I know that A-6339 and A-6340 go from the black out switch to each tail light.)

2. A-6338, as a part number, does not appear in the SNL G-529, as referenced above:
a. Is part number WEB-3695, PLUG, tail light jumper cable, assembly, in the above SNL G-529 an alternate part number for A-6338?
b. Or was part A-6338 eliminated by the time SNL G-529, 5 July 1945?

[Ben Hovis]

Chance,
I do not know what the part #'s A6338, A6639, or A6340 are. If you use the Ord 8 snl G-"529 tech manual TM10-1281 5-July 1945" and follow the wiring drawing it will work great. As mentioned before if you want a repo MBT harness they are available from Ron F. or other suppliers.
Have fun,
Ben

[Chance]

Yep, no worries Ben. All the information you've provided here already is a huge help. Bonus!

Was just trying to understand what wiring part no. A-6338 was.

[Ben Hovis]

Chance, You can get the male connector from trailer to jeep from Saturn surplus See site below. Not sure if they sell the wire that you would need. Check it out. They sell connectors too.
http://saturnsurplus.com/electrical/oldplug.htm
Ben

[Chance]

Ben I will check them out this weekend.


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[Joe Gopan]

A-6338 is the Trailer Wiring Harness described as 4 Wires in a Braded Loom. It is listed in TM10-1186, TM10-1230, TM10-1281 and all of the SNL G-529 Parts Lists. It is the main portion of the trailer wiring system that goes from the switch and connects with the rest of the wires that cross the rear of the trailer to the tail lights. I stocked these harnesses NOS in Willys and Bantam packages a few years back and they were all set up that way. (All gone now).