Hello,
I've taken apart many Bosch alternators over the years. All, after some use,
had same problem: the small ball bearing was lose in the plastic sleeve and
that sleeve would wear out the hole it was seated. As long as I had an
access to what is called in engineering as  "TOLERANCE RING" I would throw
out the sleeve altogether and install the "TOLERANCE RING", which is a ring
made of heat treated wavy strip as wide as the bearing. Fixed this way the
alternators would run for many years.
I lost the info and so far here, in Portugal, didn't find a source.
Does anyone know know who sales these rings in USA?
Ark

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