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Alternator low voltage

  • Thread starter Thread starter 69mustang351w
  • Start date Start date Jul 23, 2011
6

69mustang351w

New Member
Jul 23, 2011
1
0
0
Avon Lake Ohio
Jul 23, 2011
#1
  • Jul 23, 2011
  • #1
Hi I am new to the forum today. I have a 351 Windsor 1969 Mustang Convertible with dual flowmaster exhausts and headers. I have had the car for 8 years and it is a quality driver.

Problem: Battery went dead; jumped battery and car started; drove home on battery; car dead at home; took alternator out and brought to Autozone; Alternator failed their in store test. Bought rebuilt original equipment alternator and new regulator from Autozone; charged battery; Put all back together and car only puts out 12.5 volts. Needle on gauge shows no charge or discharge. Can anyone help? I connected the mail female wire connector; put on the 2 post power wire connector and put the third wire onto the alternator post with the rubber grommet. Then attached other wire to engine block. You can see pictures of alternator and wiring harness attached. Thanks
 

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PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 24, 2011
#2
  • Jul 24, 2011
  • #2
69mustang351w said:
Hi I am new to the forum today. I have a 351 Windsor 1969 Mustang Convertible with dual flowmaster exhausts and headers. I have had the car for 8 years and it is a quality driver.

Problem: Battery went dead; jumped battery and car started; drove home on battery; car dead at home; took alternator out and brought to Autozone; Alternator failed their in store test. Bought rebuilt original equipment alternator and new regulator from Autozone; charged battery; Put all back together and car only puts out 12.5 volts. Needle on gauge shows no charge or discharge. Can anyone help? I connected the mail female wire connector; put on the 2 post power wire connector and put the third wire onto the alternator post with the rubber grommet. Then attached other wire to engine block. You can see pictures of alternator and wiring harness attached. Thanks
Click to expand...

Hi,
I would return to AutoZone and have them test this one. If it is OK, then check your wiring schematic to verify your connections.
Good Luck!
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Jul 24, 2011
#3
  • Jul 24, 2011
  • #3
Do a "full field" test with a jumper wire at the voltage regulator. Takes only a few minutes.
 
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