My Willys 3A and 3B Community

TECH FAQ SECTIONS => Electrical Systems => Topic started by: ScottP on May 19, 2016, 12:06:13 PM

Title: 53 Cj3A Wiring
Post by: ScottP on May 19, 2016, 12:06:13 PM
Ok guys I've read the wiring diagram and other than the lights which aren't important because I am waiting on the new switch I have all the wire run to the AMM gauge, fuel gauge, etc. My problem however is this cj3a is a 12V conversion. Alternator, 12V battery, etc. I run the positive cable from the battery to the starter and a wire from the starter to the AMM gauge.....the jeep cranks a runs fine as long as the AMM gauge is hanging out of the dash...if I put the AMM gauge in the dash and start to crank it the gauge starts arching fire off the dash. Is the AMM gauge supposed to have a rubber ring or something to keep it from doing this???

I have ordered a whole new set of 12V gauges from Kaiser/Willys but I would like to make sure the wiring is correct and if the gauge is just faulty.

Title: Re: 53 Cj3A Wiring
Post by: athawk11 on May 19, 2016, 02:04:30 PM
Hi Scott,

The ammeter gauge should have 'insulators' on the studs that stop the studs from making contact with the tub.  On old ammeters, these insulators are often worn out causing the studs to ground out.  Very bad for the ammeter to ground out.  Ask me how I know this.

Sounds like you're getting a new one, but in the interim, grab an old Bic pen.  Cut some small discs  (maybe 3/16"...maybe a bit less) off the pen tube and slide them over the studs.  Re-install the gauge and you'll be good to go. 

This was a tip the Fbill gave me a few years ago when I fried the wire from my solenoid to the ammeter. >:(

Hawk      
Title: Re: 53 Cj3A Wiring
Post by: ScottP on May 19, 2016, 03:26:58 PM
Quote
Hi Scott,

The ammeter gauge should have 'insulators' on the studs that stop the studs from making contact with the tub.� On old ammeters, these insulators are often worn out causing the studs to ground out.� Very bad for the ammeter to ground out.� Ask me how I know this.

Sounds like you're getting a new one, but in the interim, grab an old Bic pen.� Cut some small discs� (maybe 3/16"...maybe a bit less) off the pen tube and slide them over the studs.� Re-install the gauge and you'll be good to go.�

This was a tip the Fbill gave me a few years ago when I fried the wire from my solenoid to the ammeter. >:(

Hawk� �� �

Sounds like you got yourself a melted wire problem just like this one had before I got a hold of it. It's actually a customer of mines. He is restoring it but does not want to fork out the moolah for a new wiring harness...the originally was toast. So I'm color coding wire and doing things myself. Considering there really isn't much wiring in these old cj3's it's fairly simple! Thanks for the tip and that explains my problem completely. There were no insulators on this gauge at all which is causing my arching problem! Thanks man!
Title: Re: 53 Cj3A Wiring
Post by: Ryan_M on May 20, 2016, 05:58:53 AM
Everyone needs at least one good ammeter fire. It's a rite of passage for all 3A tinkerers. Bonus points when it melts a brand new cloth covered wire. I have lots of points.