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Alternator / Electrical problem

  • Thread starter Thread starter rpark
  • Start date Start date Jun 24, 2005
R

rpark

New Member
Mar 22, 2003
13
0
2
Central Ohio
Jun 24, 2005
#1
  • Jun 24, 2005
  • #1
I've got a 1989 5.0 engine with a 3G 175 amp alternator installed in a "non-stang" Jeep Wrangler (all parts are new, with less than 1,000 offroad miles). Engine bay is clean (well reasonably clean).

Problem: The alternator is not always charging or working properly. At idle it works fine (14V), over 2,000 RPM's it works fine (14V). The problem occurs between 1300-2000 RPM's. The voltage drops down to 11 or so (no charging, only battery is providing electric). Now to further complicate things, after 20 minutes or so of driving with RPM's over 2000, the alternator works fine. It just seems to occur during a "warm up period".

What I've done: Installed a new voltage regulator on the alternator. Replaced the 4 gauge recharging cable.

Any suggestions?
 

BLOWN 5.0 FOX

Member
Apr 4, 2005
213
0
16
NORTH SHORE MA
Jun 26, 2005
#2
  • Jun 26, 2005
  • #2
Try using a smaller diameter alt pulley... unless you are currently using underdrives on your drive pulleys ..then scrap those. Seems your alt isnt getting the RPMs it needs to create a charge. GOOD LUCK
 
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