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3g alt acting as bad as 2g!

  • Thread starter Thread starter jammer84_03
  • Start date Start date Apr 7, 2008

jammer84_03

New Member
Nov 30, 2003
468
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0
Apr 7, 2008
#1
  • Apr 7, 2008
  • #1
well. i just purchased a 3g alt and did the swap. i have the inline fuse and everything works. the problem is, when i turn on the lights, turn on the heat, roll both windows down it seems like the alt cant keep up with the draw and the voltmeter drops big time. i went and had the battery checked and it was only reading 13.7 when i had it reving at 2,000 rpm.

i know this alt should be good enough not to have that needle budge. do i have a wire grounding out somewhere and can i test that. should i add another ground wire to the engine? i really need this amp to put out enough juice. i got my cb and valentine v1 and sirius radio as the only real add-ons.
 
N

n2o-89fox

New Member
Oct 8, 2007
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ca
Apr 7, 2008
#2
  • Apr 7, 2008
  • #2
did you upgrade the wiring?
 

jammer84_03

New Member
Nov 30, 2003
468
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0
Apr 7, 2008
#3
  • Apr 7, 2008
  • #3
yes. i did go with the 4ga from the post on the alt to the battery side on the starter solenoid.

however, i just reused the same plug from my 2g on the new 3g so i could plug the 2g back in if i need to if an issue arose like this one. i was wondering if i had the yellow wire in the correct place though. i had been doing some searching prior to my post but still want to positive on what was the culperate.
 
S

svtpower

New Member
Apr 30, 2005
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Wisconsin
Apr 7, 2008
#4
  • Apr 7, 2008
  • #4
3G

What brand alternator did you go with?
 

jammer84_03

New Member
Nov 30, 2003
468
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Apr 7, 2008
#5
  • Apr 7, 2008
  • #5
i just got a lifetime warranty from advanced auto. everything tested fine too when i had it checked. its from a 96 taurus. i had a core i took in and go the same back.

http://forums.stangnet.com/showthread.php?t=695504&highlight=3g+alternator

i was looking at that diagram in jrichker's post and saw two different things than my install, and some of the other install pics i have seen.

1) there was a groud comming from the back side of the alt. i see the spot on this alt and i do NOT have it currently hooked up. i will do that when i get home.

2) the yellow wire on the A plug goes to the post on the alt. right now i just have it staying on the plug. do i need to fuse it and have it going to the post on the alt?
 
N

n2o-89fox

New Member
Oct 8, 2007
116
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ca
Apr 7, 2008
#6
  • Apr 7, 2008
  • #6
yes the yellow wire needs to be connected to the alt it detects how many amps/volts are being put out by the alt. It just has to be hooked up to the power wire, I have mine running to the inline 150 amp fuse.
 

jammer84_03

New Member
Nov 30, 2003
468
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0
Apr 7, 2008
#7
  • Apr 7, 2008
  • #7
ok. i see that now. for some reason it didnt display the photo at home with that pic in the 3g upgrade thread. i see what i need to do now. basically it just supplying one constant supply from the alt and not upping the dose when i need it. hopefully this solves all my problems. i know its killing the performance on my car with as much drain is on it! thanks for the help
 

ShortThrow50

Member
Oct 22, 2006
923
2
16
Pa
Apr 7, 2008
#8
  • Apr 7, 2008
  • #8
i didnt even upgrade the wiring on mine and dont have that problem. weird
 
S

svtpower

New Member
Apr 30, 2005
257
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0
Wisconsin
Apr 7, 2008
#9
  • Apr 7, 2008
  • #9
http://www.corral.net/tech/maintenance/130a-tech.html has some pretty good info.

I have a PA Performance kit myself and it came with amazing instructions. I figured I'd just post a link to it on their site but apparently they charge $2.50 to download them in PDF.
 
N

n2o-89fox

New Member
Oct 8, 2007
116
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ca
Apr 7, 2008
#10
  • Apr 7, 2008
  • #10
ShortThrow50 said:
i didnt even upgrade the wiring on mine and dont have that problem. weird
Click to expand...

Until it catches on fire... But he had the yellow wire wired wrong.
 

jammer84_03

New Member
Nov 30, 2003
468
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0
Apr 8, 2008
#11
  • Apr 8, 2008
  • #11
not so much wired wrong, but more or less not switched in the first place. ran out of time last night, but i will get home early tonight to do it.

i dont really have a problem with it charging, its just when i turn on all my electronics that i run into the issues. my rd, scanners and cb really put stress on the system at ngiht when i have my lights and heater on, its even worse
 
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