6 volt Generator brushes squeal like a pig!

[ndnchf]

To compliment Terry's post, here is a set of original Ford brushes. Note that there is a chamfer at the end of the brush that attaches it to the holder. That chamfered edge should face into the corner of the brush holder to orient the commutator end of the brush properly. Some aftermarket brushes don't have the chamfer resulting in the brushes being installed backwards.

As I mentioed in my video, sanding in the brushes to match the commutator surface is very important to gain full contact. Commutator diameters vary a lot after 90+ years, so this is an important step for proper operation.
Steve