There has been some dialog recently on the 356 Registry regarding the replacement of generator brushes. This is a common wear part, and eventually, if you drive your car, you'll need to replace the brushes.
Question is- With what?
Years ago i toasted my voltage regulator and I sent it along with my generator to the electrical guru, Joe Leoni to restore them. I also had the pleasure of visiting Joe at his home in Colorado for a brief visit during that time. So, the advice below is from Joe and I am just the conduit for the message.
Always use NOS when you can. All replacement parts are not created equal. Generator brushes can be incorrect in length, because they were made for different generators/applications. The most notable of the other applications is VW, but there were others as well. This means that you cannot just see a pair of brushes on E-Bay and double click and all will be ok. If they are too short, they quickly will not do the job. To long, and you can break the spring or not even be able to install the brush.
PORSCHE had a part number for the brush, but it is not the same part number as the BOSCH part number. Joe (and now I) happen to have the BOSCH part number catalog, and the correct BOSCH part number is shown in the photos below. The photo is an NOS pair I bought a while back to have as spares for my car.
Hope this helps others in their search. You could buy replacements by looking at the standard vendors and using the PORSCHE part number, but remember, not all replacement parts are created equal.
Hope this helps.
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