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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:



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



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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

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.

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.

Thank you!

I hope it works out ok

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