Alternator Differences?

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DGriz
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Joined: Mon Nov 11, 2013 4:45 pm

Alternator Differences?

Post by DGriz »

Hi all. The alternator on my 79 528i went out, so I ordered a replacement online and went to changing it yesterday.

Unfortunately, the electrical connections are different between the two alts!

The one on the car requires 3x wire connections:

Image

The replacement has a single wire connection, and a flat blade plug in:



[/img]Image


I suspect that the large single wire (yellow/red) connection goes to the large connector on the new alt, and that the two remaining smaller wires blue & orange0 are combined into a female blade plug. Correct? Has anyone else run into this? Are these blade plugs readily available, and how are the wires connected?

Thanks- Dickson
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Mike W.
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Location: Sonoma County

Post by Mike W. »

I don't quite understand, but there should be three connections, the large brown ground wire that goes to the case, the large red wire that goes to the large terminal, and a small blue(?) wire that goes to field. I don't see any orange or two connector wire or terminal. You do still need to transfer the condenser/capactor, that smallish black device with a black wire coming out of it on the right side of the old alternator picture.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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Falkenberg
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Post by Falkenberg »

Orange seems to be connected to the ground. If so, connected it to ground (case) on the new alternator.
Do not connect it to anything else. Joining wires without knowing their function is a bad idea.

Red with the yellow connector should go to the large connector.

Blue should be field, change the connector to spade. Move the condenser (black box, black wire) (useful for filtering alternator noise) to the new alternator and you should be good to go.

I actually think that your old alternator is not stock, mine has a spade connector for field.
1961 Simson AWO sport (Brasoveanca)
1968 BMW 114 2002
1976 BMW E12 528 (Malèna)
1987 Kawasaki GPz900r
1996 Moto Guzzi V75 PA NT
DGriz
Posts: 13
Joined: Mon Nov 11, 2013 4:45 pm

Post by DGriz »

Thank you!
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Falkenberg
Posts: 520
Joined: Wed Nov 10, 2010 6:46 am
Location: In Europe, far, far away.

Post by Falkenberg »

I hope it works out ok :)
1961 Simson AWO sport (Brasoveanca)
1968 BMW 114 2002
1976 BMW E12 528 (Malèna)
1987 Kawasaki GPz900r
1996 Moto Guzzi V75 PA NT
DGriz
Posts: 13
Joined: Mon Nov 11, 2013 4:45 pm

Post by DGriz »

I'm in no hurry, so I'll employ the KISS principal and have the 3 wire version rebuilt. THANKS
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