Ammeter Going Wild

[John-T-53]

Hey all,

Last night after getting off the freeway in the truck, after about 100 miles, the ammeter gauge in the dash started going nuts....violently swinging back and forth for a few minutes while still driving. Then it calmed down and back to center after a while with a few intermittent blips every few minutes. The Truck ran fine during all this, just wondering if the voltage regulator might be going out or something. No lights flickering or anything either. The battery seems to getting charged ok too, no starter issues to speak of. Should I be concerned you think? :-/

Thanks,

[_shel_ny]

Maybe a quick look at the brushes will reveal something.

Edited November 9, 2014 by shel_ny

[Jeff Balazs]

John;

Any chance you have a wire somewhere starting to work loose? Or maybe just a dirty connection?

When an electrical problem is intermittent I always get real suspicious of any connections or switch gear in the run. Years of running a boat in salt water....and I have seen it all when it comes to this sort of stuff. I have seen what look like perfect mechanical connections fail due to moisture or corrosion.

 

Jeff

[NiftyFifty]

I agree, sounds like a loose wire, or potentially the ground point....start there before digging into the deeper stuff

[John-T-53]

Well, all of my wiring is pretty shaky, it's all original and needs replacement, however I've never had any issues really (until now...gulp). The genny brushes look good, however the sheet metal cover broke in half when I removed it. It looks like I could use a new negative battery cable though. I think it's undersized and the wires at the bat terminal appear loose in the terminal. So might see if Napa has 2/0 or 0 gauge cables. What's preferred in terms of gauge?

I've been delaying new wiring because I want to integrate turn signals, fuse box, and 12v trailer harness hookup, so until I can figure out how to do that, I'm stuck with the old stuff.

[Young Ed]

1 gauge is OEM so 0 is an upgrade and 2/0 is even more.

[Jerry Roberts]

... So might see if Napa has 2/0 or 0 gauge cables... 

 The tractor parts places also sell the heavy cables . There are still a lot of 6 volt tractors in use . 

[Jeff Balazs]

Hey John;

I wouldn't wait too long to look into this wiring. Bad connections can mean very hot sections of wire. You just might want to treat this as a friendly warning from your truck. At the very least disconnect the battery when you are not using it.....

 

Jeff

[JBNeal]

I prefer the 0 gauge...made that upgrade on the '48 and it helped with my starting issues

[NiftyFifty]

I agree with Jeff, it would be a shame to have a fire due to bad wires, or to destroy any pattern you have with what's left. Rewiring isn't a huge job, just takes some patience and good to have the diagram from the knowledge centre to go by.

[greg g]

I would check the wire that runs from the regulator to the field terminal on the genny. When you say it swings do you mean from 0 to positive or does it go into discharge also?

[John-T-53]

Good call...I really need to get the wiring thing handled before it's too late!

When the gauge was going nuts, it was swingin' left to right full tilt!

[HanksB3B]

Hey John;

I wouldn't wait too long to look into this wiring. Bad connections can mean very hot sections of wire. You just might want to treat this as a friendly warning from your truck. At the very least disconnect the battery when you are not using it.....

 

Jeff

 

 

I agree with Jeff, it would be a shame to have a fire due to bad wires, or to destroy any pattern you have with what's left. Rewiring isn't a huge job, just takes some patience and good to have the diagram from the knowledge centre to go by.

 

I MultQuote agree. It's not as difficult as you think John. If you want to save yourself a lot of time and if you've got the scratch, then a vendor like Rhode Island Wiring or Vintage Wiring of Main is the way to go. Nice as my wiring turned out, I still wish mine were color-coded cloth with soldered connections. There are 26 wires in all (stock) and if you perform wire management with wire ties and maintain an open architecture so to speak. you can get out of danger first (frayed/short prone) run your truck with the new primary and secondary wiring then add tturn signals and other auxilary wiring and add it to the wire tie loom. 

 

 

and Kudos to whoever the forum member that did this color AutoCad file with Signal Stat turn signals added

 

 

 

Friends don't let friends toast their trucks, 

 

Hank      

Edited November 10, 2014 by HanksB3B

[Jeff Balazs]

Good call...I really need to get the wiring thing handled before it's too late!

When the gauge was going nuts, it was swingin' left to right full tilt!

John;

Not everybody get's a warning like this. It is always best to pay attention when you do. Glad to see you have taken this one to heart.

 

I am certain I am not the most experienced mechanic here but I have learned to pay close attention to the warning signs I do get. It has saved my bacon more than once too. Often times it is something small like a change in the way something sounds. I have a bandsaw here in my shop that starts making a ticking sound a few moments before the blade is about to break. And it has been my experience with electrical problems that they never get better on their own.

 

The only "difficult" part of rewiring one of these trucks is getting under the dash. The runs are dead nuts simple. The work behind the dash is too......but it helps if you are young and flexible. When I was wiring my truck I actually got stuck under there once and had to have help to worm my way out. Fortunately one of my buddies showed up just when I was starting to really get worried.

 

Jeff

[Young Ed]

Good call...I really need to get the wiring thing handled before it's too late!

When the gauge was going nuts, it was swingin' left to right full tilt!

I've had this happen once in my truck and once in the coupe. The truck was the wiring under the radiator got out of place and rubbed through by the crank pulley. The car was similar I had a wire unhooked I think for the horns and it moved and ended up against metal. That one sucked it burnt my hood release cable in 1/2!

 

As the others said figure out whats up before you pull a PP

Edited November 10, 2014 by Young Ed

[John-T-53]

I MultQuote agree. It's not as difficult as you think John. If you want to save yourself a lot of time and if you've got the scratch, then a vendor like Rhode Island Wiring or Vintage Wiring of Main is the way to go. Nice as my wiring turned out, I still wish mine were color-coded cloth with soldered connections. There are 26 wires in all (stock) and if you perform wire management with wire ties and maintain an open architecture so to speak. you can get out of danger first (frayed/short prone) run your truck with the new primary and secondary wiring then add tturn signals and other auxilary wiring and add it to the wire tie loom. 

 

and Kudos to whoever the forum member that did this color AutoCad file with Signal Stat turn signals added

 

Friends don't let friends toast their trucks, 

 

Hank      

Good call, and thanks for posting the wiring diagrams. I didn't know somebody had figured it out with the turn signals too - that's awesome.

I have an old turn signal unit with a lot more wires coming outta it than the signal stat. I'm gonna try to use the old once because it looks cool (it ain't chrome). I'll dig it out and start a new thread on here. I'll bet RI wiring will know exactly what to do it I tell them what I'd like done. Besides, I'm sick of other drivers not knowing what a RH turn signal (with a hand) looks like.

[JBNeal]

Turn signals & headlight relay 

[John-T-53]

Thanks for the links...what's the spec on the headlight relay? That's a great idea!!!

[1952B3b23]

Hi John,

I can't tell you why your gauge was acting all whacky but I'm glad to hear you're tackling all the old wiring.

This past summer when I first got my plymouth coupe back on the road after purchasing it. I took it for a nice test drive the night I buttoned up the brakes. Well everything was going well until I smelt smoke and saw sparks. I pulled over and grabbed my flashlight and shined it under the hood. The previous owner had installed an aftermarket temp gauge but left the original passing through the firewall. Well it started to rub on the hot wire running to my horn. Which was still the 75 yr old wiring. So the old temp gauge wire got nice and toasty and started melting the rubber grommet in the firewall. Luckily all it did was make some smoke and didn't light anything on fire. It made me pretty nervous though, thought I was going to watch my car go up in flames. I've since replaced the bad wires and I'm glad you're upgrading your wiring too.

-Chris