Alternator not charging

billr

wrench
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Make
Ford
Model
F-150 2WD
Year
1999
Miles
unk
Engine
4.2L V-6
I had to go take a fresh battery to my son last night, meter shows no output at the stud on back of alt. I would like to check out wiring and such before throwing a new alt at it. Please post a schematic of the charging circuit, enough for me to test voltages at the alt connector. DO NOT go to great trouble to provide this, I can probably get by without, but always like to have the best info on hand. Even if it is only a VR/brushes, it will probably get a new alt. VR's are in the $60 range and I know a place to get a good new alt for $73 (delivered).
 

billr

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It is completely stock. Looking mainly for what is connected to the field/VR so I can make sure alt field is being energized properly. I see the VR has and external "ground to test" terminal, I assume that will bypass the VR and force full output when grounded; but the field supply would have to be OK for that to work.
 

nickb2

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i cannot fault this logic

It is completely stock. Looking mainly for what is connected to the field/VR so I can make sure alt field is being energized properly. I see the VR has and external "ground to test" terminal, I assume that will bypass the VR and force full output when grounded; but the field supply would have to be OK for that to work.
 

billr

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Cancel my request. The connector could not be reached with the alt installed, and once it was removed the problem was obvious; the brushes and slip-rings are ruined.
 

nickb2

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slip-rings are ruined.
shyte, I missed that.

Disregard last post if rings are too shot that emory cloth dont work, probably going to need a new unit. But knowing you, you will figure it out.

Again, happy new year to you and you significant other and family.

;)
 

nickb2

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I remember doing a few of these back when I was apprenticing, but cant for the life of me find anything in my area that actually sells these.

Cool video you can watch on mute. :p

Of note, it is a valeo alt, but procedure is basically always the same regardless. But where do you find them is the all glowing question. Maybe make your own, ;)

 

nickb2

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question, in that vid, is that a dublin accent? I am not sure. My french has hard time with accents cuz I dont think it is punjabi or something similar.
 

billr

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It is a stock (95A?) alt. Yes, I could fabricate and install new slip rings, but I would still need new brushes and would have to make them too, or get a new VR/brush "set". Since the VR/brush seems to be about $40-50 alone, and I can get a whole new alt (including shipping) for about $75, fussing with this one isn't worthwhile for me. Actually, I probably will fuss with it, but as a leisure project. I may turn it into a 3-ph PMAC motor to experiment with.
 
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