w108 280se 4.5 internally regulated alternator wiring help! - Mercedes-Benz Forum

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post #1 of 2 (permalink) Old 08-07-2012, 12:37 PM Thread Starter
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Date registered: Aug 2012
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w108 280se 4.5 internally regulated alternator wiring help!

purchased a bosch 90amp internally regulated alternator from a audi 4000/vw quantum and am going to attempt to wire it up tomorrow when it arrives. my question is this. to those of you who have upgraded to a higher output alternator, what did you do with the 3 wires going into the factory plug that plugs into the side of the alternator, and the 1 heavier gauge wire with the boot on it which i assume is for the battery connection. any ideas of how i should wire up the new alternator with these 3 wires as the connection on the new 90amp alternator does not have a 3 prong female connection on it. is it possible to just make a new cable from the alternator to the battery since the new one is internally regualted? can i just bypass and leave the old externally regulated wiring alone, or do i need to tap into that and still use it? thanks.

here is a photo of the 3 wires that go into the plug on the original alternator.
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post #2 of 2 (permalink) Old 08-10-2012, 04:16 PM Thread Starter
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figured it out, its charging! out of curiosity i "fiddled" around and got it figured out and working great. i ran a wire from the small bolt on the alternator to the red w/ blue tracer and blue wires that are joined in the plug for the voltage regulator. i made a new wire from the + terminal on the alternator and ran that to the stock junction block on the fender that the original wire bolted to. everything works and no more dim generator light on the cluster. cant tell you how happy i am to have a properly charging electrical system. the h4 autopal headlights i installed tues. are nice and bright. looking forward to going for a cruise tonight to see how proper headlights should look.
hope this info may help others with a w108 that are looking to add some more "juice" to their car.
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