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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Voltage?

  • Thread starter Thread starter 408 Beast
  • Start date Start date Sep 20, 2004

408 Beast

Member
Mar 2, 2004
32
0
6
Sep 20, 2004
#1
  • Sep 20, 2004
  • #1
I have a set of underdrive pullies and only used the crank and water pump pullies for the last 2 years, I decided to finally put on the alternator pulley yesterday, and it made my voltage drop low enough that now my battery light stays on. I was under the impression that putting on the larger alternator pulley would fix my already slightly low voltage problem.

Anyone else have this problem before, and also looking for input from others even without this problem, I'm looking for all ideas and suggestions!

Jason
 
D

Daggar

New Member
Jul 19, 2004
3,902
5
0
Sep 20, 2004
#2
  • Sep 20, 2004
  • #2
Yeah... you went the wrong way with your pulley. Putting a larger pulley on slows the alternator even more (thus your batt light stays on). Let's assume for a moment a constant idle speed. For the sake of argument, the belt travels 100 inches every second. You have a pulley that has a circumference of 10 inches. In that 1 second your alternator rotates 10 times. Now lets put on a pulley that has a larger 100 inch circumference. Now the alternator rotates only once in that second.
 

408 Beast

Member
Mar 2, 2004
32
0
6
Sep 20, 2004
#3
  • Sep 20, 2004
  • #3
ok, so changing to underdrive pullies. I changed to a smaller crank, and a bigger waterpump pully, and a bigger alternator pully, so in actuality, I have slowed down my water pump, and alternator?


That sux, but i do like them better than the stock pullies, I guess i'll go with an even smaller alt. pully than the stock one.

Thanks again
Jason
 
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