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Discussion Starter #1
Hi guys,
First timer here, so take it easy. My son has a 1965 Ford Galaxie 500. He and I are restoring it together. We have recently run into a problem where the ALT light on the dash stays on when the car is running. I have recently done some work to the car but I don't think it would have impacted it. Here's what I've done so far.


  • Replace all four shocks
  • Replace plug wires
  • Replace spark plugs
  • New points
  • New Edelbrock 1406 carb
  • New air cleaner
  • New brakes
  • New ignition switch
  • New head light switch
  • New valve covers
  • New alternator
  • New regulator
  • New brakes
  • New aftermarket radio
  • New audio amplifier
  • New speakers
  • New amplified sub woofer
  • Replaced brake hardware
  • Replaced wiper switch
I checked the light bulbs for the dash dummy lights to make sure I had not replaced them into the wrong light sockets when I replaced the switches.
All appear to be in the proper place. I just can't figure it out. Any help would be greatly appreciated.
 

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did you upgrade to altinator or did you mean generator...

new altinator/generator new regulator...

did you polarize this new combo... whont charge untill you do?????
 

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1965 saw the full intro of the ALT didn't it?

With all of the work you have done, surely you have a Shop Manual for the car. Diagnostic routines will be found there.
 

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i was thinking 64 when replying....:eek:

but if it needs polarizing....
here a link explaing about and how to do...

Polarizing Your Generator
 

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Guy's, simply remove your alternator, take it to the local auto parts store. Have them test it.

If bad get a new one. If good get a voltage regulator. 99.9% of the time you're going to be fine.

Listen not to the old ladies picking at each others posts.

WHAT did you do with the Autolite 4V carb that came off the Galaxie? I'm interested i buying it if you didn't toss it in the trash.
 

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I've had new alternators and regulators(now coming to us from the wonderful world of China) be bad out of the box. Also am finding starters totally dead NIB. I am now trying to find as many parts made anywhere but China that I can so they have a chance of lasting a while. It could also be in your wiring. If you don't have one you should get a Haynes or somebody's service manual for the car. It will have the wiring diagrams. You can also find them online and blown up. They're a bit easier on the eyeballs.
 

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Discussion Starter #9
did you upgrade to altinator or did you mean generator...

new altinator/generator new regulator...

did you polarize this new combo... whont charge untill you do?????
I don't know if it needs that but I will check and let you know.
 

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Discussion Starter #10
1965 saw the full intro of the ALT didn't it?

With all of the work you have done, surely you have a Shop Manual for the car. Diagnostic routines will be found there.
Actually I don't have a manual. I'm just going off my knowledge. I think that is the problem. I look for one and get it.
 

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Discussion Starter #11
I've had new alternators and regulators(now coming to us from the wonderful world of China) be bad out of the box. Also am finding starters totally dead NIB. I am now trying to find as many parts made anywhere but China that I can so they have a chance of lasting a while. It could also be in your wiring. If you don't have one you should get a Haynes or somebody's service manual for the car. It will have the wiring diagrams. You can also find them online and blown up. They're a bit easier on the eyeballs.
I'll check into the China production. I don't think it was made there but who knows these days.
 

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I had to re-polarize the generator on my VW buggy but I have never had to polarize an alternator. Just make sure you have the battery disconnected when you put it on.
 

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Discussion Starter #13
Guy's, simply remove your alternator, take it to the local auto parts store. Have them test it.

If bad get a new one. If good get a voltage regulator. 99.9% of the time you're going to be fine.

Listen not to the old ladies picking at each others posts.

WHAT did you do with the Autolite 4V carb that came off the Galaxie? I'm interested i buying it if you didn't toss it in the trash.
The carb that was on it is a Holley. It had issued and needed to be rebuilt. It was going to cost me more to rebuild it than the Edelbrock cost new. That's why I replaced it, but I think I still have it if your still interested.
 

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Pull-up the dash and engine compartment wiring schematics to follow the operational description that follows. If you click on the diagram, it should expand to full size for easy reading.

The basics of how the light works is that it sends voltage out from the ignition switch "A" terminal, through an inline resistor on the GRN/RED wire, to the firewall connector. The '65 Gal is a bit different than most, in that it also sends another voltage signal through the idiot light on the YEL/BLK wire to the same terminal on the firewall connector. The wires join at the connector and emerge on the engine compartment side as just the GRN/RED wire, which runs to the regulator "I" terminal.

This small +12V signal passing through the ALT bulb lights it up when the key is on, as the power is grounded through the "I" terminal of the regulator. This signal at the "I" terminal feeds a tickle signal to the alternator to begin charging normally when the engine starts. When the alternator does begin to charge, it feeds a voltage signal back out of the "I" terminal. With +12V on both ends of the same wire, no current flows, and the bulb stops glowing. If the alternator stops charging normally, the backfeed signal stops, and the bulb glows again as it is now grounding again. Bingo - alternator charge failure indication.

So, your alternator is not charging properly (test for charge voltage when running). Or, you can see that a short to ground in the indicator wire anywhere between the bulb and the "I" terminal would cause a light-on even if the alternator was charging. Or, your regulator is bad (whether charging or not) and the backfeed signal is not coming through. As FE said, have the components bench-tested at a parts store and replace anything not working right. If the bulb still glows, then you're looking for a short in the signal wiring. Good luck!

David
 

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Discussion Starter #16
Thanks for the info. Looks like I'll be busy for quite a few off days.
Pull-up the dash and engine compartment wiring schematics to follow the operational description that follows. If you click on the diagram, it should expand to full size for easy reading.

The basics of how the light works is that it sends voltage out from the ignition switch "A" terminal, through an inline resistor on the GRN/RED wire, to the firewall connector. The '65 Gal is a bit different than most, in that it also sends another voltage signal through the idiot light on the YEL/BLK wire to the same terminal on the firewall connector. The wires join at the connector and emerge on the engine compartment side as just the GRN/RED wire, which runs to the regulator "I" terminal.

This small +12V signal passing through the ALT bulb lights it up when the key is on, as the power is grounded through the "I" terminal of the regulator. This signal at the "I" terminal feeds a tickle signal to the alternator to begin charging normally when the engine starts. When the alternator does begin to charge, it feeds a voltage signal back out of the "I" terminal. With +12V on both ends of the same wire, no current flows, and the bulb stops glowing. If the alternator stops charging normally, the backfeed signal stops, and the bulb glows again as it is now grounding again. Bingo - alternator charge failure indication.

So, your alternator is not charging properly (test for charge voltage when running). Or, you can see that a short to ground in the indicator wire anywhere between the bulb and the "I" terminal would cause a light-on even if the alternator was charging. Or, your regulator is bad (whether charging or not) and the backfeed signal is not coming through. As FE said, have the components bench-tested at a parts store and replace anything not working right. If the bulb still glows, then you're looking for a short in the signal wiring. Good luck!

David
 

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I gave you one of the simplest routes to take when finding out what's the issue. It's most likely the Regulator or alternator or a broken wire....

You find anything out? Did you simply put a multimeter on the battery while the engine was running to see what voltage you had?

Wish we could make it easier for ya.
 

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assuming all is well and the altinator is charging (and maybe if its not). there is one small possibility.

could possibly be a warn out ignition/key switch.

try (after starting) 'jiggling' the key in the ignition. by moving the position of the key in the ignition, the 'current' could not be grabbing, and/or the key is not fully returning to its assumed position after starting.

on my 64 ford pickup it does just that. after a jiggle the generator light (even though its been converted to alternator) turns off.

either way good luck.
 

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The carb that was on it is a Holley. It had issued and needed to be rebuilt. It was going to cost me more to rebuild it than the Edelbrock cost new. That's why I replaced it, but I think I still have it if your still interested.
Depending on which Holley it is I might be... If ya still have it tho....
 
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