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Alternator not charging - need help!

Slewis25

New Member
Joined
Jan 7, 2008
Messages
13
I have read through some of the recent posts and determined that my alternator is working but is not wired correctly. I was checking to see if anyone might have some input or a wiring diagram they could send me. I have a 69 with a 302, there are two wires that attach to the top of the alternator and plug into the harness, there is another connection towards the bottom of the alternator that also goes into the harness and to a ground on the fender. I have 12 volts at the battery with the engine runing or not. I put a screwdriver to the back of the alternator shaft with the engine running and the shaft was definitley magnatized. Any help would be great.
 

NMWILLY

Jr. Member
Joined
Jun 22, 2007
Messages
135
Loc.
Hendersonville, NC
If it's a stock alt and harness then the White with black stripe wire goes to the Stator (STA). White is field (FLD). Black is BAT and the black with red stripe is ground.

Does your gauge show charging?

Check your regulator as well. If the alt is producing then the regulator is not letting the power go to the Battery.

Good luck!
 
OP
OP
S

Slewis25

New Member
Joined
Jan 7, 2008
Messages
13
Thanks for the input, thta wiring diagram is exactly what I was looking for. I have changed the voltage regulator and the wiring appears to be correct. The gauge on the dash still reads 0 and I still have only 12 volts at the battery when the engine is running.
 

Madgyver

Contributor
Bronco Madman
Joined
Jul 30, 2001
Messages
14,679
Check your belt tension.
It may need to be alot tighter than you think.
 

70_Steve

Old Guy
Joined
Dec 13, 2002
Messages
8,317
Wire 37 (Black w/ Yellow stripe) is the output of the alternator. It should have 12 volts on it all the time. Makes a loop through the ammeter and back out, through the fuse link, to the BAT side of the starter solenoid. Wire 35 (Orange) is the Field connection. That comes from the voltage regulator, and determine whether the alternator will charge or not. With 12 volts on the Field connection the alternator will charge. No 12 volts, no charge.

So... What voltage do you have on the Field connection?
 
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