Alternator Hmmmmmmmmmm
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,815
Likes: 470
From: Wichita Kansas
Alternator Hmmmmmmmmmm
I searched for this problem and solution but only came up with problems with radios that hum. So what is going on with the '72 is that my alternator crapped out so I replaced the diode, voltage reg, brushes and capacitor and cleaned it up. It works great now except that it hums. Before it crapped out, it did not hum. Hmmmmm.....
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,815
Likes: 470
From: Wichita Kansas
So the radio is causing the alternator to hum? even with the radio is off?
oh, and GO ALASKA lived there for 3 or 4 years as a tot.
oh, and GO ALASKA lived there for 3 or 4 years as a tot.
Last edited by kansas123; May 23, 2012 at 08:31 AM. Reason: Cuz
Le Mans Master
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the part that the brushes ride on is the comutator, there are separations 'those small lines', the 'mica', that fill with crud from the brushes, rebuilders will clean those out with a small dremel like grinding wheel, it makes it work better and last longer. I take a small pick or knife and manually scrape them out, have to be carefull not to scratch the surface.
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the part that the brushes ride on is the comutator, there are separations 'those small lines', the 'mica', that fill with crud from the brushes, rebuilders will clean those out with a small dremel like grinding wheel, it makes it work better and last longer. I take a small pick or knife and manually scrape them out, have to be carefull not to scratch the surface.
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You could also have a belt or pulley issue. I chased an alternator hum for almost a year. It was a bad (out of round) pulley.
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Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,815
Likes: 470
From: Wichita Kansas
i suspected this all along
So to put a fork in this..........it turned out to be a small vacuum leak, not the alternator. i was trying to put all the load on the alternator that i could so i was turning on everything and when i turned on the wipers, (even though they are mainly vacuum operated), the noise went away. thanks for all the inputs though....