external voltage reg. problem

[derek528]

I converted to an external regulator because my pcm is bad and I am having problems with it. I'm using the '89 dodge regulator. The problem I'm having is at an idle the volts surge between 14.5 to 15 volts constantly. It's a steady surge and when I am driving, it charges a little over 15 volts which I think is to high. The gen light is also on and I believe it's because it is overcharging.
Thanks for any help.

Derek

 

[RonA]

Mopar blue is the only one that works in my truck. Even they only last about 8 months to a year. The regular ones won'y work right out of the box.

 

[derek528]

I'm thinking that alternator is higher amp than what the regulator is designed for. I might try an adjustable one I found on ebay.

Thanks

 

[mondtster]

I'm thinking that alternator is higher amp than what the regulator is designed for. I might try an adjustable one I found on ebay.

Thanks

The regulator only controls the field switching. The amperage output that the alternator is capable of should make no difference.

The old Chrysler voltage regulators use the case of the regulator as the ground reference. That means that you had better have the regulator bolted down to a good clean metal surface and that the body of the truck needs to be grounded well.

I have heard a lot of complaints about the parts store (aftermarket) regulators being junk, which could be part of your problem. The blue regulators that RonA mentioned are intended for race purposes only, so I have never tried one. Chrysler does offer the standard regulators as well so I would suggest trying one of them first and seeing what happens.

Charging in the low 14 volts range seems to be normal, but 15 sounds a bit high IMHO.

 

[derek528]

I sanded the paint from the mounting area and secured it with three screws. Charging is still in the low 15's. I had napa test the reg. and the machine showed it to be good.

 

[BlackSkyRacing]

I use a regulator off of an 86 F350 with a 6.9... Can't remember the part number right off hand. But it's been working flawlessly for almost 2 years now. Though, mine charges around that 14.5-15v area.