Volts drop when idle?
Former Vendor
Joined: Apr 2009
Posts: 766
Likes: 3
From: Charlotte North Carolina 704-394-5150
If you are using under drive pulleys...the problem will persist unless you change teh pulleys back. If not..it sounds like the alternator or the connections to it may be loose or wires broken or a loose belt.
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Race Director
Joined: Feb 1999
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From: Lenoir City Tennessee
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Idle speed can also affect output of the alternator. The alternator is not going to put out the same voltage at 600 RPM vs 2500+ RPM while cruising.
Racer
Joined: Mar 2008
Posts: 428
Likes: 0
True but, voltage at idle must be at least 1 volt above battery voltage (13.5 or 13.6) and that's where the regulator comes into question.
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
Most likely you need a new alternator as most people have stated, but it'll be a good idea to also check your fan belt tension and also check the big cable on the alternator as well. That cable goes all the way to the battery behind the driver seat and could corrode over time.
Old guys like me call it trouble shooting, the new term is root cause analysis. Same difference, you figure out what is not working the way it should and fix it.
Le Mans Master
Joined: Aug 2006
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From: mount holly NC
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Why would you replace the entire alternator when just the regulator can be replaced? In fact, most all the parts in the alternator can be replaced. Check the Service and Overhaul manuals for testing & repair instructions. Check the vendors for the parts.
Old guys like me call it trouble shooting, the new term is root cause analysis. Same difference, you figure out what is not working the way it should and fix it.
Old guys like me call it trouble shooting, the new term is root cause analysis. Same difference, you figure out what is not working the way it should and fix it.
But the auto parts stores offer a lifetime warranty, I went to AZ when the regulator failed and years later a bearing failed so I'm sold on lifetime warranties. PG.
