Charging issue/voltage regulator

93superduty

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Let me start by saying anything electrical is a foreign language to me so any help would be greatly appreciated. I recently bought a 93 f super duty idi and am having an issue with charging. I replaced both battery’s and at and idle my gauge shows a good read. But as soon as I started to drive the gauge pegs at 18v. This led me to the external voltage regulator on passenger fender. I can not find the original part anywhere and unfamiliar with what new external one I should buy and how to wire it. Any help would be awesome! Following is pictures of original.
 

dgr

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Welcome. Can you post a pic of your alternator for us?
 

dgr

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I asked my friend Google. That there is a charge light relay for an ambulance package. Probably an 165 amp alternator.

I'm going to guess that pretty hole in it is a symptom and not a cause. Is this what your alternator looks like?

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93superduty

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That is correct that is exactly what it looks like!

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dgr

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That rectangular box on the back is the voltage regulator. It's considered internally regulated. You get one at the parts store. I'd pull the whole alternator, take it to a rebuilder and ask them to test it. My concern would be blown diodes in the alternator.

Sorry I don't have more info for you. Hopefully someone else has info specific to your charging system.
 

dgr

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I dug around for you a little. This is a Leece Neville alternator. Which means there is a lot of info available on it. But it's a little complicated if electricity isn't fun for you.

The white plastic screw is a cover plate that hides the regulator adjusting pot. As part of the diagnosis steps, that can be adjusted.

There is a diagram in this thread showing that relay you posted. https://www.oilburners.net/threads/big-alternator-wiring.70020/

It looks like a guy with some crimpers could replace that with a bosch relay. The alternator signal wire would connect to 85. The charge light wire would connect to 87a. 86 and 30 would connect to ground. With the key on, the indicator lamp would light. Once the alternator supplied power to the relay, the light would go out.

@franklin2 and @MIDNIGHT RIDER know a thing or two about these alternators.

Good luck
 

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