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Discussion Starter #1
I put in a new alternator and regulator this last weekend and am now having nothing but problems. I wired everything back the way the PO had it when I did the changeout (I wasn't having problems until it stopped charging my battery saturday morning). Since then, when the car is charging, the ammeter is pegged to the C and it won't ever drop. the battery does charge but has a slow drain and will become useless fairly quickly. Could the Alternator or voltage regulator that I just bought be bad? And if so, which sounds like the most likely candidate with what I've described? Is there some easy test I can run with a standard volt/amp meter to diagnose this?

I also went to my shop manual and checked out the wiring. It looks like they had different wiring setups depending on whether the car has a dummy light or a real guage. I guess what I want to know is can someone describe for me how a 66 with ammeter guage is wired at the alternator. Mine currently has nothing going to the STA post.

Thanks in advance...

Chris
66 Coupe
 

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Black/yellow line to red connection (Bat)
white line to white connection (field)
red-black to chassis ground (GND)

STA not used.
 

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One thing to remember.....Just because it is new, doesn't mean it is good.....sounds like regulator.......
 

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Look for loose or weak ground connections. Had a similar problem on my '66. Poor negative battery cable connection. Check block to body cable and anything else you can find that might be a poor connection. Good Luck
 

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Discussion Starter #5
Thanks to all that replied. I'm trying a new (again) regulator in a few minutes since it is the easiest to change out. I'll look into the wiring more this weekend if that doesn't solve the problem. I also feel a lot better knowing I hooked the alternator up correctly! /forums/images/icons/smile.gif

Chris
 
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I'm in the process of restoring a 1966 Mustang Convertible and have a lot of literature that I use to try and put my car back together with. I have a book composed of original Ford drawings showing the proper way to do all of the electrical on the car and I just happen to be at that stage of the restoration so I sympathize with your plight.

The Ford Electrical drawings show that their is a harness that attaches the Alternator to the Main Headlight Harness. The connections at the alternator end have four (4) leads.

A. Black-Red Stripe - 2
B. White
C. Black-Yellow Stripe

The 2 Black-Red Stipe wires are ground leads one attaching to the alternator and the other to the engine block. The other 2 leads attach to posts on the alternator c. to the outside post and B. to the inside post.

This harness plugs into the main headlight harness which in turn connects to the voltage regulator.

Hope this helps.
 

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I'll second the voltage regulator. I had a problem with very similar symptoms. I'll also
suggest that if this new VR doesn't improve the problem, go get a solid-state regulator
from any of your local parts stores. It may not be original and you don't have to keep it
in the car, but it will help diagnose the problem more reliably. The original style VRs
are prone to problems, even when new - believe me, I have 2 on my shelf that were brand
new and didn't work right.
 
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