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alternator question

  • Thread starter Thread starter dkins419
  • Start date Start date Aug 19, 2005

dkins419

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Nov 14, 2004
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Michigan
Aug 19, 2005
#1
  • Aug 19, 2005
  • #1
alright i went through 2 stock 75 amp alternators in a month. Is it just the alternators? Im not running anything special like a electric fan or subs or anything. Could maybe something with the wiring be wrong? Im gonna upgrade to a 130 amp alt. but i just want to make sure so i dont ruin this one or run into another problem. What should i do or check? or should i nto worry about it?
 

HISSIN50

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Aug 19, 2005
#2
  • Aug 19, 2005
  • #2
What has the failure been on the alts? Reman'd units from the parts store? Or decent units (new)?

Good luck.
 
T

TheUser

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Jul 25, 2003
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Aug 19, 2005
#3
  • Aug 19, 2005
  • #3
do you know what part of the alt specifically has been going out? You know you can get a kit and rebuilt them yourself right? Not very hard to do...takes prob. half an hour or something, maybe a little more depending you mainly. But since you're getting a 130amp, nevermind.

What I would do first is look for any visual defects in the wiring and check the fusible link wire that attaches the alt wire to the starter solonoid. I believe the alt wire is black/orange 10ga and it is connected to a brown 14ga fusible link wire about 6" down from the solonoid. I had to replace my fusible link which was in horrible shape and I believe it's what actually cause my voltage regulator to fry and, of course, my alt wouldn't charge.

Now, if it looks ok, you should use a voltmeter and check the resitance of that wire...very much resistance and you need to replace it.

Good Luck
 

HISSIN50

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#4
  • Aug 20, 2005
  • #4
Good ideas from James. Remember too that if you are going with a 3G, you can omit the stock charging cables (using the term 'cables' loosely). That leaves the D-plug wires and stator wire as things to check.

Good luck.
 

jrichker

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#5
  • Aug 20, 2005
  • #5
Here's websites with pictures of the 3G installation...

See http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm - all the tech data you could ever want to know
OR
http://www.mustangcentral.net/tech/alternator.html - excellent pictures of installation

Use these sites for information on the right way to do the wiring. Some people will tell you that you can skip the wiring upgrade, but it will catch up with you sooner or later. A fire in the wiring harness is ugly and expensive.

Under no circumstances connect the two 10 gauge black/white wires to the 3G alternator. If the fuse blows in the 4 gauge wire, the two 10 gauge wires will be overloaded to the point of catching fire and burning up the wiring harness.

Electric fan = 3G alternator if you want long life & reliability from your car.
The electric fan saves some HP. The stock fan's parasitic drag runs from 7-12 HP depending on who you talk to. The electric fan uses about 1/2 HP of power from the electrical system.

Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!

See WWW.partsexpress.com for the fuse & fuse holder.
Fuse @ $3.90 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=071-952

Fuseholder @ $5.80 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=263-630

4 gauge black wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-196

4 gauge red wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-194

4 gauge ring crimp terminals (package of 5) $3.25. http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=095-584

Don’t forget the alternator power ground!!!
The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.
 
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