Alternate Alternator Options/Sources

Talk and Tech about turbocharged 924/944/968 cars
cda951
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Darwin wrote: Fri Feb 28, 2025 3:15 am Just found out that my single wire alternator was the source of a significant battery drain. Self exciting single wire alternators are known for this, I guess...I recently swapped back to an OEM unit and my problem completely disappeared. Just for info, in case anyone else is looking at going to a single wire alternator.
Yeah, single-wire alternators are for tractors, they at some point crossed into the aftermarket as an "upgrade" with idiot-proof wiring, which is great for a very simple '32 Ford hot rod, not as great for a car with modern engine management, high-wattage headlights, stereo, etc.

Good info here:

http://www.madelectrical.com/electrical ... wire.shtml
Chris A.
---'86 944 Turbo track rat
---'90 944S2 Cab daily/touring car
---'73 BMW 2002tii road rally car
---'81 Alfa Romeo GTV6 GT car/Copart special
---'99 BMW Z3 Coupe daily driver/dog car
---'74 Jensen-Healey roadster
---other stuff

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Darwin
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cda951 wrote: Fri Mar 07, 2025 9:38 pm
Darwin wrote: Fri Feb 28, 2025 3:15 am Just found out that my single wire alternator was the source of a significant battery drain. Self exciting single wire alternators are known for this, I guess...I recently swapped back to an OEM unit and my problem completely disappeared. Just for info, in case anyone else is looking at going to a single wire alternator.
Yeah, single-wire alternators are for tractors, they at some point crossed into the aftermarket as an "upgrade" with idiot-proof wiring, which is great for a very simple '32 Ford hot rod, not as great for a car with modern engine management, high-wattage headlights, stereo, etc.

Good info here:

http://www.madelectrical.com/electrical ... wire.shtml
If only I knew this before I went through all the trougle of converting! Now I have a nice paperweight for an alternator with no real way of unloading it!
1984 VW Rabbit Pick-up - Not stock
1988 944 Turbo S - Really not stock (Chris White special)
2012 VW Tiguan - Kinda stock
2013 Cayenne Base - 6 Speed! Tastefully modified, mostly stock

#52

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Darwin
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dme wrote: Fri Mar 07, 2025 3:32 pm
Darwin wrote: Fri Feb 28, 2025 3:15 am Just found out that my single wire alternator was the source of a significant battery drain. Self exciting single wire alternators are known for this, I guess...I recently swapped back to an OEM unit and my problem completely disappeared. Just for info, in case anyone else is looking at going to a single wire alternator.
When my Nissan alternator failed it would drain the battery while sitting overnight. I have a lifetime warranty on my Autozone Nissan/Mercury alternator so the failure didn't cost me anything but time for R&R.
This has me curious if I have a failure or not, but my alternator has less than 2k miles on it and I bought it probably 8 years ago from autozone in UT (now I live in CA) I swapped back to stock and my voltage is fine and my problem is gone. Hopefuly someone can learn from all of this!
1984 VW Rabbit Pick-up - Not stock
1988 944 Turbo S - Really not stock (Chris White special)
2012 VW Tiguan - Kinda stock
2013 Cayenne Base - 6 Speed! Tastefully modified, mostly stock

#53

chrischrischris
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I didn't know that any 944 had a "check engine" light.

#54

SirLapsalot
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chrischrischris wrote: Wed Apr 09, 2025 11:58 am I didn't know that any 944 had a "check engine" light.
Not sure what model years it was first introduced with, but the dash cluster I installed in my car and is shown in the picture earlier was from an 87 parts car I had. The original dash in my 86 did not have the check engine light IIRC.

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stitch2k1
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So what's the good source for an alternator? Straight from Nissan? Plus where to buy a 6 rib pulley for it?

Did that new bracket get made?
Porsche 944S2 5MT '91
BMW E39 540iT 6MT '00
Mercedes-Benz W201 190E 2.6 5MT '89
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fasterfaster
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edit: NM, decided to keep my Nissan alternator for a later install.
Last edited by fasterfaster on Mon Jan 26, 2026 1:24 pm, edited 1 time in total.
Marc
88.5 951 M030 Red on Black

#57

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rheidtman
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For those looking to retain the OE Bosch 90A/115A alternators, I now have all the parts and cores to start rebuilding.
Yet another on the endless list of parts I rebuild... Drop me a note if interested.

Rick
Oak Creek, WI
1989 951
1989 928
2015 Panamera Turbo S

#58

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stitch2k1
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rheidtman wrote: Sat Jan 24, 2026 8:54 am For those looking to retain the OE Bosch 90A/115A alternators, I now have all the parts and cores to start rebuilding.
Yet another on the endless list of parts I rebuild... Drop me a note if interested.

Rick
Oak Creek, WI
What's your price on rebuilds? My car needs the smaller alternator, but I've got plenty of cars that just need a regular one.
Porsche 944S2 5MT '91
BMW E39 540iT 6MT '00
Mercedes-Benz W201 190E 2.6 5MT '89
IG: @stitch2k1

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rheidtman
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My rate for a 90 or 115A OE Bosch alternator is $375, plus a core charge of $300. My preference is surely to receive the original alternator back to allow continued rebuilding....

Sadly, yes, these alternators are now getting crazy expensive. A quick review of Pelican shows a rebuilt unit is now over $1300 with a hefty core charge... 944 Online has been out of stock for months...
https://www.pelicanparts.com/More_Info/ ... DID=282971
1989 951
1989 928
2015 Panamera Turbo S

#60

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