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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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alternator putting out too much juice

  • Thread starter Thread starter gsxrocky
  • Start date Start date Mar 3, 2004
G

gsxrocky

New Member
Jan 18, 2004
13
0
0
Conroe, TX
Mar 3, 2004
#1
  • Mar 3, 2004
  • #1
alternator putting out too much juice. Help please

I put a new alternator in my 89. It worked fine. Then I bypassed the smog pump. It started putting out 17-18 volts. Fried the battery. I thought the voltage regulator was bad. Tested alternator and it did act funny. They gave me a new one for free as well as a new battery. Got it installed and it still reads 17-18 volts. Any ideas. I don't want the battery to blow under the hood. Thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Mar 4, 2004
#2
  • Mar 4, 2004
  • #2
too much alt output is a first for a fox. i dont know but am interested to see what you all think. i would be lookin for a bad diode in the alt, but if it is new and the old one did it, i dont know.
good luck.
 
S

StreetStang37

Founding Member
Apr 23, 2001
451
0
0
San Jose, CA
Mar 4, 2004
#3
  • Mar 4, 2004
  • #3
im still thinkin its your voltage regulator. maybe the new one they gave you was bad too. im thinkin you can damage more than just the battery with that much voltage.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Mar 4, 2004
#4
  • Mar 4, 2004
  • #4
SS is right. if the amp output corresponds to the increased voltage, you could be heating the marginal wire from the alt to starter solenoid.
also make sure you have the yellow/white wire in the alt wiring. it helps regulate voltage.
 

Black 93 Fox

Active Member
Jun 1, 2003
1,995
0
49
Vancouver,Washington
Mar 4, 2004
#5
  • Mar 4, 2004
  • #5
Mine did this for a while, I couldnt figure it out espicaly since I have underdrive pulleys on. So I ignored it but about 2 weeks ago it was hardly charging at all. The the next day I had to get a new alt havent had the problem since I got the new alt.

Black 93 Fox
 
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