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The problem that I'm having is when ever I turn on lights,Heat,or any accessories the voltage go down to the red how do I need to try to fix this problem or do I need to get a stronger alternator.
 

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What year/model is it? You can always take your car to AutoZone and have the alternator checked for free on the vehicle. You may need a new one, if you do (depending on your application) you can upgrade to a stronger one.
 

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Have you resently added any electricial items to it? Stereo or something?
 

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Are you running underdrive pulleys? That usually makes the charging system problems worse.
Anyway, check out these sites for more info:

http://www.racesystems.com/3gproj/
http://www.aircapitalmustangs.com/techtips/techtips.htm
http://www.fordmuscle.com/archives/2001/03/paperformance/

This would probably be your best bet, and get 130 amps out of the deal. I did this on my '73 351C, I'm running an electric fan, A/C, high output halogen headlights, EFI, and other odds and ends and mine has never skipped a beat. I got mine from AutoZone from a '95 Mustang Cobra with a 5.0 with a lifetime warranty.
Hope you get it figured out and good luck, Chris.
 

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Sounds to me like your voltage regulator is fried.

Change it.
 

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On 2007-01-02 19:45, FALCONAROUND wrote:
Sounds to me like your voltage regulator is fried.

Change it.
That would be located inside the alternator on an '88 mustang.
Take a voltmeter reading across the battery terminals when the engine is running. It should read 14.5 volts. Anything lower indicates a charging problem.
 

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If, in changing the regulator you must remove and replace the alternator, then do it and stop talking back or I'll send you to your room this very instant!

If his lights dim and the meter drops into the red when trying to run some accessories then the internal reg is shat.



FE
 

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May as well upgrade if you're replacing it.
 

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I too like the notion of getting a higher than stock amperage alternator to run modern electrics. How did you get the AutoZone from a '95 Mustang Cobra with a 5.0 with a lifetime warranty to fit your '73? Isn't there the serpentine pulley vs. v-belt pulley difference and what about the mounting ears? I like what you did and would like to try something similar with my Ranchero.
 

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I used this link as reference:
http://tinyurl.com/l2vsb
I used (2) 6-10 inch pieces of 12ga fusible link wire (NAPA) in place of the mega fuse (Ford used this for years).
For the pulley, I got a double pulley from the junkyard and swapped it out, you can probably use a single groove, but the double is heavier duty. All the pulleys lined up perfectly, I threw on a new belt, and gave it a try. The voltage went from 12.8V stock to 14.35V, that is always good.
The only major mod to the alt. was on the small ear, I tapped it and put a helicoil in it to reuse the factory alt bolt.
My car came with the small case alt. (no power anything) so the swap was a breeze, and it looks like it belongs there.

Chris
 
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