Generator Brushes - Proper Prodedure

Good evening. I was getting my 81 XJ-650 ready for spring. I put the battery in, gave her some choke and she fired up. So, I decided to do my generator brushes since it's listed as standard maintenance in my factory service manual (Even though they don't list procedure in the book) I removed the cover, came off easy, removed the old worn brushes, replaced them with the new ones, lined up the wires in the rubber grommet in the slot in the cover and put everything back together. Then I turn the key and It blew the main 20 amp fuse, so I replaced the few, and it blew it again ! So, I removed the cover again and I notice that the brush holder is loose and as soon as I loosen it the one ear cracks off. I figured that something wasn't lined up right and when I consulted the service manual I concluded that something was was grounding out. Which would explain the broken tab on the bush holder grounding it's self against the generator case and causing the main fuse to blow. What is the proper procedure to install the new brushes so this doesn't happen again.

 

Compare your replacement part to the original.

If they aren't a direct replacement, then something's not right. The "procedure" is simply to replace the old with proper new parts, and carefully tighten the screws a little at a time on each one until the assembly is tight. You can't crank one side fully tight while the other is still fully loose, you might break something.

There are only two screws; unless you got medieval on it, you might not have the correct part.

Were the old brushes worn past the lines, or the little braided lead wires corroded green?

The book says 10K, mine are still fine after 27K and 17K respectively. Did you actually need to change them?

Did you replace the alternator cover gasket with a proper (now solid aluminum) one?

 

I'm not quite sure what happen, one of the many joys of working on old things. Something maybe was to tight. The new parts looked the same as my old parts. The old brushes did seem to be worn. I ordered a new brush holder and going to source the gasket as well. Thanks for the help !