Does a 400 really need two altenators, or would one modern unit work? I was on Jay Leno's web site and he said that he replaces the altenators in his classics with a modern one.
I think the reason for the 2 alternators is that the dinoplex is very sensitive to over and UNDER voltage. If you had only 1 alternator and it went out it might damage the dino
That would be a pretty unusual engineering solution to a dinoplex design problem, but who knows, maybe its true. I always thought that the two 55 amp alternators were because (i.) a 110 amp alternator was too big to fit anywhere in front of the engine (ii.) a 110 amp alternator was not produced by Bosch at the time, or (iii.) Luigi had a storeroom full of 55 amp alternators and doubling up on the 400i was a good way to work down the supply. I do know that the car ran fine on one alternator when one of the other belts broke a while back. I would not recommend running it like that for long and would replace any broken belt asap.
If your alternator needs rebuilding (low voltage output) it is very easy to rebuild. The regulator/brush assembly takes about 2 minutes to swap once you get the alternator out. The part is readily available from a Bosch dealer and cost about $40 or maybe less. Ken
