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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Charging system

  • Thread starter Thread starter Max Power
  • Start date Start date Jul 28, 2005

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Jul 28, 2005
#1
  • Jul 28, 2005
  • #1
It's been a while, and my Ford Shop manuals suggest using all sorts of equipment that is special use Ford stuff from 1969.

I think I have a charging problem. It's a 69 with a recent 393 upgrade. I replaced just about everything during the upgrade, including the battery, solonoid, regulator, alternator, and cables. Grounds are as factory, although I would like to get an extra ground hooked up somewhere.

Voltmeter reads 12.1v at idle at the battery. Shouldn't it be about 13.8?

How do I seperate the regulator from the alternator to test the alternator? Just unplug it while running?

It's been about 25 years since I actually had to diagnose anything in these systems
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Jul 28, 2005
#2
  • Jul 28, 2005
  • #2
Pull the regulator plug off and jump the hot lead to the alternator (probably yellow) with the field lead (two terminals away) using a meter or wire. The alt should go to full charge (engine idles down). If this happens then the reg is bad. If not then the alt isn't working right.
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Jul 28, 2005
#3
  • Jul 28, 2005
  • #3
Thanks Krash, found the problem. It was an open Field wire in the harness between the alt and the reg.

I love cheap fixes!
 
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