Alternator Not charging?

CamaroBoy07 · Oct 5, 2012

Hey guy's,
So I have a 67 Rs with the original 327, and have no power flowing out of my alternator. Here's the fun part, I 1st went to have my alternator tested, which turned out to be good, so I then swaped my voltage regulator with a 68 chevelle, same problem of only 12.5v's coming off of the alternator. So i then thought the place that I had test it had a bad tester, So I went out and bought a "New" (re-built unit) and installed it only to find the same symptoms are present. I checked all my fuses, all good there, I have ran down all my wiring, no present detachments or exposed wires. This is an "all of a sudden" on set problem. Fired her up the day prior with all systems working and normal only to find the next day 12.5v's coming off the alternator with no (at least with my experience) reason as to why. Thanks in advance, and Any and All advice is appreciated

Everett#2390 · Oct 5, 2012

Be sure the ground strap for the VR chassis is in place.
If GEN light goes out with engine running, VR is working and so is alt.
The red wire connections, all of them, should be disassembled and wire brushed, reassembled.
If GEN light does not go out, then no field voltage (blue wire at alt connector) from the VR. Broken wire?
With engine running, lay a screwdriver across the rear bearing of alt and you should feel a magnetic pull on the screwdriver.

CamaroBoy07 · Oct 5, 2012

Ok I forgot to mention that I have console gauges and I don't have the gen light. But I did lay a screwdriver over the back of the bearing with no feel for a magnetic field.

DjD · Oct 5, 2012

There is an excitor wire that runs from the voltage reg to the alt. This wire only has voltage when the key is held in the start position and starts the alt charging. If you are not getting voltage on this wire (key in start position) a tested good alt won't start charging.

CamaroBoy07 · Oct 6, 2012

That sounds like it might be my problem!, where is that wire? Or better what color?

69-Pace · Oct 6, 2012

The Field wire is dark blue and marked as F on the Voltage Regulator connector.
Both the Blue and White wire from the VR connection go up to the rear of the Alternator in the standard factory 3 wire charging setup.
The third wire on the Alternator is the red lead heading to the junction block.

madmax87 · Oct 6, 2012

My exciter wire is currently bad so in the meantime just to get the alt excited is to take it to 4K and that will turn it on. You may want to try that for a quick test.

CamaroBoy07 · Oct 7, 2012

4k? Not understanding... But I would Really Like 2, I have been contemplating how to "excite" ;-) lol the alternator, but it sounds that u already have one?

madmax87 · Oct 7, 2012

Drive down road and either take it to 4000 rpm's or put in clutch or neutral and rev it up. Most alternators will turn on at the point.

CamaroBoy07 · Oct 9, 2012

Ahhh I will def try that and let u know

Alternator Not charging?

CamaroBoy07

Everett#2390

CamaroBoy07

DjD

CamaroBoy07

69-Pace

madmax87

CamaroBoy07

madmax87

CamaroBoy07

Top Contributors this Month

Recommended Communities