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Re-Man OEM style Alternators PROBLEMATIC?

RM23M9A

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During the course of a recent engine rebuild, repaint. Alternator from E Bay (Yes I know ), Alternator construction causing a "Short-to-Ground" with POS Field wire connection. Must one really spend $300?! Are Classic Industries Alternators OK?
 
I guess you're looking for something brand new and "concourse"?
Heck, the standard ol' 55 (46??) amp rascals a lot of these cars came with can be had
at any parts store remanned for like $35 with warranty and they're fine in my
experience.
 
Well, not really "Concourse", but as OEM as possible. I know from experience, you can buy a reman Alternator, install it, and only get 5 volts from it, on occasion. Thry don't put alot of work into making them "New" for $40.
Im sure it's my luck, or might have an issue OTHER than the alternator. New Dash AND engine wiring, (M&H) from Year One. 440 Six Pack, new battery. 2 TOTALLY Different "Brush Designs" causing a SHORT with field wire.
( I do know, the one on car needed an Insulating Washer), but that didnt help. It still shorts-to-ground, shutting down motor.
20210224_041957.jpg
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that brush insulator change ( brush itsefl is the same yet ) was made on later squarebacks design... the ones C shaped one got with this side view

7024.jpg


Stator completelly hiddend down the case.

they are also a bit wider and bigger diameter, by a couple of mm
 
about problematic? actually never have had a problem about voltage fails, but durability.

the short you got is because the insulator washer was repplaced by a metallic one to make it work as a single field alt. That's not factory setup, but modification by seller

20210224_041957.jpg


which is fine to make to make it work with older regulator system, but if you are not aware of that OR you upgraded your charging system to a dual field and bought an alternator per year setup ( 69 was single field ) the seller will send you the correct alt round back single field or a later alt dual field with a grounded brush. And without clip off or bent the brush prong to prevent the wrong connection you can make that mistake... still being a mech reg system!!!!!!


This is the correct setup

alt brushes.jpg
 
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Yep, looks like thats the issue!
Guess the GREEN wire or ground is just tied out of the way with the grounded alternator.. Pain in the arse..
 
about problematic? actually never have had a problem about voltage fails, but durability.

the short you got is because the insulator washer was repplaced by a metallic one to make it work as a single field alt. That's not factory setup, but modification by seller

View attachment 1074244

which is fine to make to make it work with older regulator system, but if you are not aware of that OR you upgraded your charging system to a dual field and bought an alternator per year setup ( 69 was single field ) the seller will send you the correct alt round back single field or a later alt dual field with a grounded brush. And without clip off or bent the brush prong to prevent the wrong connection you can make that mistake... still being a mech reg system!!!!!!


This is the correct setup

View attachment 1074245

Crazy part is, it's a 69 Model year with a 71 charging system..lol At least the Ammeter works..lol
 
Yep, looks like thats the issue!
Guess the GREEN wire or ground is just tied out of the way with the grounded alternator.. Pain in the arse..

The deal with the green wire is on earlier single field alt it handles positive, while on dual field is negative... or the return to the regulator which grounds out that side if you want to be more specific. IN BOTH CASES, the green wire is the regulated source, but diff field. Sooo if you were hooked up the dual field wiring with green wire to the grounded brush and the blue wire to the isolated brush the only fail you was got is a full fielding alternator at max output. But backwards, well, the short you got

IF you still had the single field wiring and which uses a green wire only ALSO ATTACHED to the intentionally grounded brush, you were got a short. So in both cases you needed to know the brush was intentionally grounded, and it should have clipped off or bent to prevent that
 
The deal with the green wire is on earlier single field alt it handles positive, while on dual field is negative... or the return to the regulator which grounds out that side if you want to be more specific. IN BOTH CASES, the green wire is the regulated source, but diff field. Sooo if you were hooked up the dual field wiring with green wire to the grounded brush and the blue wire to the isolated brush the only fail you was got is a full fielding alternator at max output. But backwards, well, the short you got

IF you still had the single field wiring and which uses a green wire only ALSO ATTACHED to the intentionally grounded brush, you were got a short. So in both cases you needed to know the brush was intentionally grounded, and it should have clipped off or bent to prevent that

Basically, doing away with the steel washers on BOTH terminals is "The FIX"..I guess
 
yeap to match your setup, that's the fix. And get the propper isolation washer. The washer is a need... But if both got steel washer that was COMPLETELLY WRONG!!! lol... THAT WAS A CAUSE A SHORT ON ANY SETUP ... LOL
 
yeap to match your setup, that's the fix. And get the propper isolation washer. The washer is a need... But if both got steel washer that was COMPLETELLY WRONG!!! lol... THAT WAS A CAUSE A SHORT ON ANY SETUP ... LOL
Haha... As I figured! Buying alternators from so called "Pros" on E Bay strikes again!
 
Look for a local rebuild shop that does good work. Take all your alts and starters there. Tell your friends, Keep them in business. I know this just depends on where you are. Some shops are good some are not.
 
Best reman electrical items are from the mother ship. Mopar remans are done to factory spec with ALL QUESTIONABLE PARTS REPLACED. They don't just toss one brush in and call it done. The factory has to stand behind the warranty due to costs that could happen after its sold or installed at a dealer. Parts store remans are not a good idea. The "lifetime warranty" doesn't mean poo when you are forever replacing it.
 
What would you turn to next, if 2 alternators shorted like this?
Good grief!
 
We've been working this rabbit hole for a month now. I'm at a loss as to why you haven't simply removed the screw(s), thrown away the metal washers and isolated the spades from the case??.. so that both field spades are isolated from the case and you can use that two wire regulator. The first alternator only needed one done yet you chose to ignore that advise and went out and bought another alternator. Now you have one that was improperly assembled with both spades grounded out on it. At least the first one was done correctly, to make it work, for MOST '69 system with one lug grounded out. All you had to do was isolate that lug and you'd be driving her.
 
Well, not really "Concourse", but as OEM as possible. I know from experience, you can buy a reman Alternator, install it, and only get 5 volts from it, on occasion. Thry don't put alot of work into making them "New" for $40.
Im sure it's my luck, or might have an issue OTHER than the alternator. New Dash AND engine wiring, (M&H) from Year One. 440 Six Pack, new battery. 2 TOTALLY Different "Brush Designs" causing a SHORT with field wire.
( I do know, the one on car needed an Insulating Washer), but that didnt help. It still shorts-to-ground, shutting down motor.View attachment 1074231 View attachment 1074232 View attachment 1074233 View attachment 1074234 View attachment 1074235
Remind me not to ever fetch one from wherever you've been getting them then. :)
(Yes, I suspect other things may be happening there - these old alternators are quite simple and have a reputation for being quite resilient if not taxed beyond their design or otherwise handicapped).
 
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We've been working this rabbit hole for a month now. I'm at a loss as to why you haven't simply removed the screw(s), thrown away the metal washers and isolated the spades from the case??.. so that both field spades are isolated from the case and you can use that two wire regulator. The first alternator only needed one done yet you chose to ignore that advise and went out and bought another alternator. Now you have one that was improperly assembled with both spades grounded out on it. At least the first one was done correctly, to make it work, for MOST '69 system with one lug grounded out. All you had to do was isolate that lug and you'd be driving her.

Yeah, I tried hooking up the one that was working ok before a small fire. It shorted. I'll need to just order the stronger spacers etc, screws could be overtightened as well I suppose? I'll give that a try.
Dunno why they have 2 differently designed cases for same part. Manufacturers I guess.
 
Best reman electrical items are from the mother ship. Mopar remans are done to factory spec with ALL QUESTIONABLE PARTS REPLACED. They don't just toss one brush in and call it done. The factory has to stand behind the warranty due to costs that could happen after its sold or installed at a dealer. Parts store remans are not a good idea. The "lifetime warranty" doesn't mean poo when you are forever replacing it.
Where to find a TRUE MOPAR Alternator though?!
 
Kansas City doesn’t have any private rebuilders that can go through your original alternator?
 
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