Hey guys. I have had nothing but issues with my alternator since I got the damn thing. First I replaced the brushes. Worked fine for a while. Then the other day I replaced my plugs, wires, cap, and rotor. Ran perfectly for a day. Then driving at night a noticed my lights get dim. Then I hit a bump, and they brightened up and my voltometer read just under 14 again..... Damn brushes again......right? Nope.
With the engine running I touch a screwdriver to the pulley and it sticks to it......so it's working fine, or so one would think. I drove around town today as I have some things to do. Doing so I had to stop and start it a few times, thinking that it would just murder my battery but it didn't? It reads 11 volts. Won't go any higher but it doesn't go any lower either??
Has anyone ever had this issue? Any help would be great! Thanx guys!

 

This is a unique problem?

 

I think the fact that it came back on or after a bump is your big clue. Look for a loose ground or a loose connection somewhere. It is likely that your alternator is fine, the wiring is the issue.

You can run a long time on the battery if it's getting enough charge while the engine is running. A voltmeter isn't telling you much, the ammeter tells if your charge from the alternator is more than needed to run the engine and recharge the battery.

I would pull the alt and take it to a shop to be tested, at least in most cases that is free and you can rule that out as the issue. Then start with the wiring and a VOM, looking for loose connections.