'52 M38 Wiring Questions

paynzer · Post by **paynzer** » Mon Jul 19, 2010 1:59 pm

Hey Wes, was working on ground wires for the instrument cluster per your diagram, but my volt gage only has one terminal on it. Where the other terminal should be there is only a smooth plastic covering???

Jeeps4Brains · Post by **Jeeps4Brains** » Mon Jul 19, 2010 8:38 pm

The AMP Meter would use two wires. The Volt Meter only measures the system voltage and uses one wire. The current travels through the meter to the gauge body to the ground.

paynzer · Post by **paynzer** » Mon Jul 19, 2010 8:47 pm

Thanks, I thought I was going crazy. Had to take the front passenger fender off tonight just to get the old battery ground cable off... both the bolt head and nut were stripped and it was frozen together after all these years. After trying every tool in my box and using all the 4 letter words I knew I gave up and removed the fender. I bet the old motor pool aces took the fenders off as soon as one rolled in to be worked on. Over an hour of my life to remove one bolt !!!... don't you just love old jeeps !!!

Post by **wesk** » Mon Jul 19, 2010 9:36 pm

Most of the voltmeters had a pigtail (either metal Douglas or rubber Packard type) for the positive and a screw on terminal for a ground. If yours does not have the negative terminal then all the more important to add the ground wire.

paynzer · Post by **paynzer** » Mon Jul 19, 2010 10:16 pm

How should I ground my volt meter? I've seen the ones with the negative terminal screw, but mine does not have one. All it has is a packard connector and nothing else.

Post by **wesk** » Mon Jul 19, 2010 11:42 pm

You just use one of the two mounting studs.

paynzer · Post by **paynzer** » Tue Jul 20, 2010 5:34 am

OK, good...I connected ground wires to my gages per the diagram and ran one to the firewall. Should be good to go.

Thanks.

paynzer · Post by **paynzer** » Thu Jul 22, 2010 12:52 pm

Well I struck out on the old style mil turn signal switch. Saturn sent the distributor box, but did not have the switch so I am back to looking at turn signal systems. If I use a civvy switch such as a sig stat 900 will I need to use a 24v flasher?

Also, on the regulator harness, is wire 15 a 12g wire before it becomes wire 11. In other words, is the first run of wire 15 a 12g wire?

Post by **wesk** » Thu Jul 22, 2010 10:32 pm

I wouldn't give up on the old M series system yet. I believe you can make a civvy 900 switch work with the old system relay box.

There's a few inconsistencies with the M38 wiring diagrams. The manuals are written with out enough attention to the changes that occur when you delete the circuit breakers.

Without the circuit breakers I believe they go this way:

You should have 10 ga on wire # 10. At the double connector you will go to 12 Ga on #25 and #11. then when #11 splits to the switch and #15 starts #15 should be 12 Ga.

paynzer · Post by **paynzer** » Thu Jul 22, 2010 11:17 pm

Thanks Wes, i was just looking at the signal stat 900 on the NAPA site. The switch I was looking at is about $50.00 and comes with a 7-wire harness. I would love to be able to hook it up to the mil dist box if you think it possible, paynzer.