The alternator in my '73 450 SLC has developed a high pitched squeal
when its first started up (cold). It goes away after a few seconds.
Took the alternator apart and the bearings appear to be OK, but I
packed them with some grease anyway. One thing I noticed was the
copper commutators had deep grooves in them where the brushes
ride. This doesn't seem right. Does anyone know if this is the way
Bosch alternators are supposed to be?
Other alternators I've had apart are very similar, but the wear occurs
in the brushes, not the commutator.
p.s.-after greasing the bearings, I still have the same problem