Not charging

[19 69 GTX]

Bought a car yesterday and it's not charging. Not sure if it's the alternator or external regulator. The picture I posted is that a regulator it doesn't look the the old ones I'm used to. It's on a 68 roadrunner . Got to be the alternator or regulator the battery is new. Thanks

 

[Don Frelier]

If it has a Dual field alternator one terminal needs to be grounded.

 

[AR67GTX]

That’s an odd voltage regulator to me also. I think I would try replacing it first.

 

[Don Frelier]

You can jump across the two connectors as a test.
If you get charging the alternator and field connection (s) are correct and you need a new regulator.

 

[19 69 GTX]

If it has a Dual field alternator one terminal needs to be grounded.

Yes one is grounded

 

[19 69 GTX]

Just wasn't sure if the picture is a regulator or not. Never seen one like it.

 

[HALIFAXHOPS]

It is a prestolite constant output same as the blue DC ones used for racing. Prestolite made them for Mopar in the day. I actually have one of them new.

 

[59pwrwgn]

Direct Connection soldone like that. It was blue in color like this one. I had this on my car for awhile but I think I read in a magazine it was for racing and wasn't good for long term use. Not sure if that was true but I switched to the 70s style. You need to make sure you had a good ground to the fire wall.

 

[Black_Sheep]

I had one on the GTX for years, it’s an electronic regulator. There was an adjustment screw on the back side to dial in the voltage.

 

[68BabyBlue]

Direct Connection soldone like that. It was blue in color like this one. I had this on my car for awhile but I think I read in a magazine it was for racing and wasn't good for long term use. Not sure if that was true but I switched to the 70s style. You need to make sure you had a good ground to the fire wall.

View attachment 1694715

I ran one of those for 100,000 miles in my '62 Imperial, converted to electronic ignition when it was my daily driver, never had any trouble.

 

[19 69 GTX]

I ran one of those for 100,000 miles in my '62 Imperial, converted to electronic ignition when it was my daily driver, never had any trouble.

Well alternator checked out fine and battery is new. Ordered a new regulator like the blue one pictured above from Summit Racing. Hopefully this takes care of the issue. If not next would be a wiring issue.

 

[Don Frelier]

See post #4.

 

[19 69 GTX]

See post #4.

So unhook the two wires on back of alternator and run a jumper from one field to the other field wire?

 

[Don Frelier]

No disconnect the regulator and put a temporary jumper accross the two connections.
It should charge fully, if it does then the regulator must be defunct.

 

[19 69 GTX]

No disconnect the regulator and put a temporary jumper accross the two connections.
It should charge fully, if it does then the regulator must be defunct.

I did that. Unhooked both wires from regulator and bypassed regulator and still not charging. My alternator has one green wire going to field and the other filed connection is grounded to body of alternator. What gives

 

[AR67GTX]

My alternator has one green wire going to field and the other filed connection is grounded to body of alternator. What gives

That sounds correct for a dual field alternator installed on a 66/67. That blue regulator is not a good idea on the street.

 

[0DegreeEngineer]

You can jump across the two connectors as a test.
If you get charging the alternator and field connection (s) are correct and you need a new regulator.

place a jumper from the FLD to GND and remove the regulator from the circuit correct?

 

[RJRENTON]

place a jumper from the FLD to GND and remove the regulator from the circuit correct?

No....disconnect the regulator. Jump from battery+ to UNGROUNDED field terminal/wire....alternator will change at max. If yes, replace regulator if not, alternator MAY have a bad diode. Full load test the alternator according to FSM...NOT THE AUTO PARTS STORE METHOD....JUST MY OPINION...
BOB RENTON