Posted by Sherman in Idaho [24.32.202.166] on Thursday, April 18, 2013 at 03:20:15 :
In Reply to: Re: OT but MOpar posted by Kaegi [24.16.253.154] on Wednesday, April 17, 2013 at 18:47:54 :
It's definitely not charging at low RPM, but it's possible that alternator/regulator combination never did. My 67 Chevy has always acted as you describe, despite replacing alternator and regulator. The old DC generator systems never put out current at idle speed, so perhaps the engineers and customers considered it acceptable for the early alternator systems as well. It's also possible the alternator is week. Alternators have 6 diodes in them, and if one fails (not uncommon) it will reduce your output but it will still work okay at higher speeds. You can check them yourself with an ohm-meter but you have to unsolder one end of each to check it, which is a hassle.
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