'52 M38 Wiring Questions

paynzer · Post by **paynzer** » Fri Jul 16, 2010 5:22 pm

Still working on wiring the '52 m38 with no circuit breakers, and could use some help with a few things:

1) What is the route of circuit 10 after it leaves the v.regulator? it seems to split several times, and I want to make sure I have done this correctly. I split it to the horn (25), to the light switch main feed (15) terminal at "F", and to the ignition switch where it split again into the "A" and "C" terminals. Seemed like alot of "Y" junctions, but that is how I understood it. I used 14g wire for these circuits.

2) Trailer coupling: What letters on the trailer coupling do the tail light wires enter? And what happens with 24a and 24b at the coupling.

3) Tail lights: I want to install "goat" lights for better visibility. How will I wire the right side which also has 3 wires?

4) Volt meter?: I am using a volt meter? with color codes instead of an amp gauge. It only has one terminal connection. Someone in the know told me to splice circuit 8 & 9 together and put the 5th wire of my spider harness into the volt meter. Sound OK?

5) Should the fuel tank be grounded?

6) Also, just to hit on the idea of a stupid question, can you use a 2-1 adapter to connect just 2 wires, or do all the terminals need to be connected?

I feel like I am "sleeping" with my jeep these days.

Thanks for all your time and help, paynzer.

paynzer · Post by **paynzer** » Fri Jul 16, 2010 8:23 pm

Hey, I figured out where the tail light wires enter the trailer coupling (amazing what reading the manual for the fiftieth time will do !!) but I am still unable to figure out where the 24 wire splits to go to the trailer coupling. The picture in the manual is very small and shows a bunch of mingled dotted lines inside of a rectangle??? If someone has a clearer picture or a clear explanation of this circuit I would sure appreciate it. Thanks, paynzer.

Post by **wesk** » Fri Jul 16, 2010 10:23 pm

paynzer wrote:Still working on wiring the '52 m38 with no circuit breakers, and could use some help with a few things:

1) What is the route of circuit 10 after it leaves the v.regulator? it seems to split several times, and I want to make sure I have done this correctly. I split it to the horn (25), to the light switch main feed (15) terminal at "F", and to the ignition switch where it split again into the "A" and "C" terminals. Seemed like alot of "Y" junctions, but that is how I understood it. I used 14g wire for these circuits.

2) Trailer coupling: What letters on the trailer coupling do the tail light wires enter? And what happens with 24a and 24b at the coupling.

3) Tail lights: I want to install "goat" lights for better visibility. How will I wire the right side which also has 3 wires?

That depends on weather you are running turn signals and if you are which system are you using?

4) Volt meter?: I am using a volt meter? with color codes instead of an amp gauge. It only has one terminal connection. Someone in the know told me to splice circuit 8 & 9 together and put the 5th wire of my spider harness into the volt meter. Sound OK?

#8 & # 9 read the shunt in the old style (mechanical) regulator. Do not wire them together (they can then discharge your battery during long periods of inactivity). The volt meter was normally installed when the Army installed the later style transistorized regulator which had no internal shunt for an amp meter. To power your volt meter you should buy a 5 wire spider (this is wire #27 assembly) and connect one leg of the spider to each gauge and the 5th leg to the #27 power feed from the switch. Then attach a ground wire to the volt meter's negative post and run it to the firewall and fasten it there for grounding.

5) Should the fuel tank be grounded?

Yes and it pays to add a wire from one of the sender bolts to the tub.

6) Also, just to hit on the idea of a stupid question, can you use a 2-1 adapter to connect just 2 wires, or do all the terminals need to be connected?

The connector won't fasten securely without two connections on the double side. Just add the second wire to the double side and dead end it.

I feel like I am "sleeping" with my jeep these days.

Thanks for all your time and help, paynzer.

Here's a few more that will help. Make good use of the several hundred reference photos you'll find on my photo storage site.
http://wsknettl.mypicgallery.com/

In this photo the top right amp meter will be replaced with a volt meter and you will use a 5 wire spider harness from a M35 to connect switched power to the volt meter. Don't forget to add a ground wire for the negative post of the volt meter.

paynzer · Post by **paynzer** » Fri Jul 16, 2010 11:16 pm

Hey Wes, thanks so much for the info !!!

I am not running turn signals as of yet...just want to get gama goat lights working bright.

What do I do with the 8 & 9 wires if I do not splice them together?

What size wire would I use for the ground jumper you diagramed in the instrument panel?

Could you help me with the wiring diagram symbols. Sometimes 2 wires join and there is a shaded rectangle at the junction, and other times there is just a black dot. I think I know what it means, but I do not wish to assume...

So the 10 wire circuit branches to the horn (25) circuit, the light switch feed (15) circuit, and the ignition switch (11) circuit where it pigtails again into the A & C terminals of the ignition switch? This is how I have it wired as of today with no circuit breakers. Am I headed in the right direction?

Many thanks for all your help, paynzer.

Post by **wesk** » Sat Jul 17, 2010 1:11 am

Turn signals will save your bacon some day. They are a simple add on and you can use the Civvy 900 series switch.

You can dead end 8 & 9 or remove them from the harness.

This is how the #10 power wire from the regulator should run on late models w/o CB's.

Use the same gauge wire for a ground as the gauge of the power wire would be. IE Gauge 16 power gets a 16 ground. The last segment from the gauge cluster to the firewall or dash should be 14.

The little boxes usually represent the metal Douglas connectors and the box with the X in it should be the male Douglas metal shell and the box without should be the female shell.

paynzer · Post by **paynzer** » Sat Jul 17, 2010 7:59 am

Thanks again Wes...I was up till 3:30 this morning looking at your pics...this stuff is addictive !!! paynzer.

Where can I get a Civvy 900 turn switch kit?

Post by **wesk** » Sat Jul 17, 2010 8:37 am

NAA, Carquest and etc. There is a civvy 24 volt truck unit available as well. But the 12 volt unit will work using a 24 volt civvy flasher and pilot lamp.

Scott21 · Post by **Scott21** » Sat Jul 17, 2010 9:20 am

Here it is

http://www.midwayautosupply.com/showpro ... teid=10050

Scott

paynzer · Post by **paynzer** » Sat Jul 17, 2010 9:28 am

Thanks for the info on the turn signals...was just going to get her back to stock, but Wes makes a good point about hwy safety these days so might as well add the turn signals while in wire mode. paynzer.

Post by **wesk** » Sat Jul 17, 2010 10:11 am

Yep this is the time to add them along with those full red lens.

You have several options for adding that right stop lamp function. Keep in mind that for turn signals you will need a separate service stop lamp wire for left and right. You can run a new wire from the turn signal switch to the right service stop lamp or you can just use the original right BO stop lamp wire. If you want to keep her stock as much as possible then run a separate wire.

paynzer · Post by **paynzer** » Sat Jul 17, 2010 11:17 am

OK Wes, you talked me into it, now please talk me through it. I completely gutted my old wiring so I have no wires at all going to the rear of the vehicle. I have also removed my old tail lights to install gama goat lights from saturn surplus. I have installed the light switch harness and have all my wires (16g as I mentioned in a previous thread) labeled sticking out into the engine compartment. I have no wire(s) at all for turn signals, only 21, 22, 23, and 24 (which I understand pigtails off of 20)? None of the headlights or marker light circuits have been wired yet either...waiting on parts...all I have ready so far is circuit 10,12,15,27,and 40 using your diagrams. I have the original front marker lights which I can use as front signals. Please help me understand how to wire all this up provided I use a civvy turn signal kit and gama goat lights. Also, how much more involved is it to install a military signal kit? Thanks again, paynzer.

Post by **wesk** » Sat Jul 17, 2010 3:09 pm

That would give you all three of your turn signal options.

1-Install civvy 900 series turn signal switch and flasher.

2-Install early military relay box type system.

3-Install later military transistorized system.

I think you'll find the best bang for your buck with the Signal-stat 900 series

paynzer · Post by **paynzer** » Sat Jul 17, 2010 7:48 pm

Hey, my jeep has the old style mechanical voltage regulator (auto-lite). Can I still use a new volt meter wired like previously discussed or will I need to get an ammeter and use wires 8,9. I know this may sound dumb to you mechanical guru's (not to mention any names Wes), but I am very new to all this and want to be sure before I proceed with all the fun stuff.

Post by **wesk** » Sat Jul 17, 2010 7:54 pm

The only purpose for those two wires is to operate the amp meter. Dead end or remove them and press on with a volt meter. The actual power is moved thru the shunt down in the regulator.

paynzer · Post by **paynzer** » Sat Jul 17, 2010 8:12 pm

When I made my harness from the voltage regulator I split wire 10 to wires 11 and 25 with a soldered pigtail, screwed on a wire nut and taped tight. Is this ok or should I have used 1-2 connectors? I am not wiring under the dash for show prizes, but I do want the wiring to function safely and properly. Thanks, paynzer.

'52 M38 Wiring Questions

'52 M38 Wiring Questions

Re: '52 M38 Wiring Questions

volt meter question