when the voltage reg goes,smoke smell?

[andy74]

i was driving my charger home last night,hedalights heater and wipers on,when i got a whiff of melting plastic smell,then no charge on the alternator.would the reg shitting the bed do that?

[Ghoste]

It could I suppose but I'd be checking under the dash for the source of the smell.  I'd start with the bulkhead connector. 

[andy74]

the bulk head connecter seems fine,and i dont see any obvious burned wiring,i noticed the last 3 nights when the car was idling with the heater on that the amp out put was pretty low,but it moved up to normal when i gave it a little gas.any ideas?

[Ghoste]

I'm guessing that it doesn't normally do that so it means there is too much resistance in the circuit someplace.  You said the alt isn't charging anymore, does it still run?  Your car is electronic regulator correct?

[andy74]

yes it still runs, i drove 22 miles on the battery! i was at work,i already locked the doors and my cell phone was dead,talk about a shitty time to have an issue.i unhooked the battery last night,just to be safe,and didnt try it today.but like i said,it went from charge to no charge,and a minor wiff of smoke smell,and i drove it all the way home,with just the headlights on.(thank god for rain ex) it does have the electronic regulator also

[Ghoste]

In 74, all the power still goes through the ammeter right?

[andy74]

i guess?

[Ghoste]

And it was a plastic, burning insulation kind of smell?   Wiring is melting someplace.  You have to find that first.  Everything in the fuse box is good?

[andy74]

ill check it out when i get home,post here tommorow(i hope,its cold as hell today!)

[Chargen69]

I had three voltage regulators go bad on my other 69.  None of those smelled when it happened. 

[andy74]

well its not the regulator, i changed it out yesterday,and i dont want to start swapping parts to see whats up,its to damn cold in the driveway.so i charged the battery and im going to drive it to work,and get it into the shop,where there is heat!! if its the wiring harness i have a used one i bought off ebay,its in great shape.i guess ill see what the hell is wrong now,time to park her for the winter anyway

[andy74]

i think i discovered the issue,there is a burnt spot right up tight to the amp guage,in the back of it-what the hell would cause that?

[Ghoste]

Old wiring, high load, too much resistance=heat.

[greenpigs]

I would clean all the contacts..they should have some in the shop. Then I would check for spliced wires as this is all to common on old harnesses.

[twilt]

i think i discovered the issue,there is a burnt spot right up tight to the amp guage,in the back of it-what the hell would cause that?

Andy, that is VERY  common on our cars. I cant tell you how many Rallye  clusters that  i have bought,  that the rear of amp gauge or the whole amp gauge was toasty. check the condition of the  isolator material around the ammeter posts.  they commonly deteriorate causing a  direct short to ground via the cluster frame which is grounded to the dash frame. if you pull the amp gauge out of the cluster, there should be isolating material (little rectangles-with 2 holes for amp gauge posts to go thru ) on both sides of the cluster frame.  If i ddnt expalin that good enough, let me know and i`ll post some pics.   

[twilt]

Andy, here is some pics of the ammeter.  1st pic with ammeter still in cluster. note the fiber insulator below the retaining nuts.

[twilt]

2nd pic with cluster face removed. note that there is another fiber insulator on the front. the posts on the ammeter are "hot" so they MUST be insulated from the dash frame. the fiber insulators can crack/deteriorate/fall out over time, if one of the posts contacts the dash frame, you
got fire and smoke.

[twilt]

3rd pic ammeter removed

[twilt]

close up

[twilt]

my advice..........pull the cluster, remove the switches, bezel, and face lense. completely remove ammeter and inspect it for heat damage and bad insulators. BTW.., when i went out to my barn looking for a cluster to take pics of, i noted that i have 5 of them that are complete, some even with tach that are missing amp gauges because they were toasted or missing when i got them. its common, real common. good luck!

[andy74]

cool Tom,thanks alot-i am planning on pulling my guages out over the weekend,and ill check it all out-my question also,can i by pass the ammeter,and run a aftermarket voltmeter?if so,how do i go about it?sounds like this is my issue,and like i said in my pm,i dont plan on driving her again until spring-unless work gets really bad,then ill be heading south,and ill probably drive her down!

[twilt]

Andy, thought you might fund this interesting. I think this is what nacho did to his car.
http://www.allpar.com/fix/alternator.html

[twilt]

and here is the link for bypassing the ammeter.
http://www.robdiesel.com/techinfo/Cars/ampgauge.htm

[Nacho-RT74]

yes that's the same I did but I used heavier wires.

http://www.dodgecharger.com/forum/index.php/topic,6441.0.html

I had the wiring upgrade long time ago ready on my car but just a few days did the alt upgrade.