voltage regulators

[Hansen01]

ok so the local parts man is getting frustrated with me and my warrentied voltage regulators, i was getting the cheap light duty ones, but switched to the heavy duty one after about 4 of them went out within a year. so i get a heavy duty one and it only lasts a month. what gives??? should there be something else i need to look into about why it is eating so many regulators so quickly?

[Tacoclaw]

Make sure you have the key off when you install them. From what I gather in the instructions arcing them will ruin them. You could unplug the battery completely when you install it if you want to make sure.

Make sure your connection is clean at the plug in as well. I ran a dedicated ground from the body of the regulator back to the battery post, but I never had any real mystery failures so I don't know if it'd help you or not.


What is your truck doing that makes you suspect the regulator? It just stops charging or over charges?

[BobS]

These old trucks develop an intermittent cab ground problem. This results in creating a voltage spike to the voltage regulator. The voltage regulator is a solid state device which uses an integrated circuit and transistors. These components fail when subjected to intermittent voltage spikes. Run a good ground lead from the negative side of the battery or from the rear of the engine block to the cab firewall. Grease the attaching contact points. Use solder on ends if possible. Also use tooth style locking washers under the bolt heads. Chrysler engineering could have used the third unused position in the voltage regulator plug for a ground circuit but opted to save about twenty cents per truck by omitting it completely. Just another of those save now and pay later engineering designs.

[Hansen01]

When the regulators go out it always overcharges the system and blows fuses and all that crap

[Hansen01]

ok, so thanks guys for the replys, i ran a ground from the battery to the firewall behind the regulator, sanded down to metal where it grounds to the firewall, and had my regulator tested, it tested good, so i put it back on and still the same old crap, so i put on another one that worked once in a while and the ground helped it out enough to at least drive it. The other day i replaced the plug that goes into the regulator and i think that this helped the most. so if anyone is haveing troubles with there regulators i suggest getting a new plug(napa has them) and running a ground to it

[skilletky]

viewtopic.php?f=30&t=11553

I recently added a relay from the batt to the blue wire going to the regulator as described in the link above and it fixed all my problems I have ever had with the charging system.

[Hansen01]

ok, thanks, il have to try this if i have any more issues, trucks down for a couple weeks now while the pumps getting rebuilt

[cougar]

When the regulators go out it always overcharges the system and blows fuses and all that crap

Clue!
Your regulator acts as a variable resistor to ground for the field winding of the alternator. In order for the alternator to "overcharge" the battery, resistance on the - side of the field has to get reduced or grounded. I would be looking at the wire between the alternator and regulator and see if it is shorting to ground. There is also the possibility the short is internal to the alternator.

[Hansen01]

alternator is almost new, but i added a ground and a new plug to the regulator, and i think that the plug helped the most if anyone else is having problems.

[Mark Nixon]

The green wire on the regulator goes DIRECTLY to the field on the alternator, so there is only 1 potential problem spot on the ground side of the regulator.

FWIW, in my ventures to the yards I always keep my eyes out for older Mopar vehicles with the regulators that have the Mopar logo or brand on them, as I have found that even a 20-odd year old, "worn out" regulator is way better than the highest priced JUNK these parts stores are pushing on us these days.

I fairly recently had a regulator go bad on the old flatbed, at 9:PM at night, in BF Arkansas.
I tore the whole truck apart and couldn't find the spare and I needed headlights, so knowing that the green wire is a switching ground, I rigged a system through the blower switch (variable resistance) and made it to a place with a parts store (200 miles) to wait 'till it opened up.
To operate the alternator, I flipped the blower switch to half speed, then pushed the "HEAT" button and waited until the voltmeter's needle spiked to full, then flipped the HEAT switch off to cool a few seconds, then repeat.

This was a fairly slow climb, and what I was doing was using the blower's resistance coils (located behind the ABS module) to slow the charge rate, so as to not overload and boil out the battery.
It wasn't a kosher repair, but it did the trick and I could probably have gone clear across the country that way.

Mark.