Bad Alternator? NO, BAD VOLTAGE REGULATOR

[Got2Gnow]

I've got my Dart "stored", up on jack stands, for the winter. While "stored" I start/run the vehicle for about 30-45 minutes (running through the gears (A904) putting about 2 1/2 miles on the odometer).

Yesterday I started/ran the vehicle as usual. While watching my volt gauge it never left the 10-12V range. Normally as the RPMs increase the volt gauge will increase up to the 12-14V range.

The battery is/was fully charged (battery tender in use) and was replaced in June (2014).

I did the AMP gauge bypass (MAD Electrical) several years ago. All connections are clean and tight.

The alternator has been on the vehicle as long as I've owned the car (~11 years).

What do you guys think?

 

[Inertia]

I have a quick-check method for on the road..

Turn on the key,, take a screwdriver or wrench,, hold it to the front of the alt pulley,, if the alt sucks the tool to the pulley,, the regulator, brushes and connections are good,, so problem is likely the rectifier in the alt..

If no magnetic attraction,, the connections, brushes or regulator are the problem..

Take the green field wire off the alternator,, and ground that alternator spade/connector .. ,, if you get magnetizm, then everthing in the alt is okay and you need a regulator..

I often check it running to discount the brushes making intermittant contact,, CARE MUST BE TAKEN while running..

hope it helps

 

[Got2Gnow]

OK, I tried the magnetic pull test with key "on" engine "off". There is NO magnetic pull.

I then started the engine (volt gauge still showing 10-11V). I tried the magnetic pull test again, NO magnetic pull on the front or rear of the alternator.

Looks like I'm buying an alternator.

I see AutoZone has a 50A or a 65A unit. I assume the 65A unit is the one I want/need (A/C car)? :???:

 

[pikewi]

65A. Have the parts store test your old alt. just to be sure

 

[Got2Gnow]

Did some troubleshooting with RapidRobert (from Moparts.com). Check out the backside of the Voltage Regulator photo:

 

[pishta]

Might want to pony up the $25 for a new one...Make sure its grounded at the mounting point. Slap some dielectric grease on the back of the new one if its exposed like that.