Alternator problem ?
Thread Starter
Heel & Toe
Joined: Mar 2009
Posts: 19
Likes: 0
From: Broken Arrow Ok.
Alternator problem ?
I have been having a battery drain problem. Unhooked the negative post and put a tester between it and the battery, the light on the tester lit up. Took all the fuses out and light still lit, unpluged just about everything elese light still lit. When i unpluged the alternator the light went out. Is alternator bad or is that normal. 
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
I have been having a battery drain problem. Unhooked the negative post and put a tester between it and the battery, the light on the tester lit up. Took all the fuses out and light still lit, unpluged just about everything elese light still lit. When i unpluged the alternator the light went out. Is alternator bad or is that normal.
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
Have you tried starting the car normally, with the alt. connected, and then disconnected? If the car cuts off, your alt. is bad. Another thing someone told me was to start the car and touch the back middle part of the alternator with a screwdriver, if it magnetizes that supposedly means the alt. is good, I have tried this method and I think it wors
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Racer
Joined: Dec 2009
Posts: 380
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From: Glendale AZ
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Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
I guess we assumed that you knew how to check a drain at the alternator. I also guess that assumption was wrong. Now we are making an assumption as to just what year car we are working on. All of these factors make it difficult to advise you. If that car has a courtesy light dimmer, I would unplug the controller and see if the problem goes away.
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
Have you tried starting the car normally, with the alt. connected, and then disconnected? If the car cuts off, your alt. is bad. Another thing someone told me was to start the car and touch the back middle part of the alternator with a screwdriver, if it magnetizes that supposedly means the alt. is good, I have tried this method and I think it wors.
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Thread Starter
Heel & Toe
Joined: Mar 2009
Posts: 19
Likes: 0
From: Broken Arrow Ok.
the car is a 1978. i dont think it has a dimmer for the courtesy light but i will try and find it. i dont have a tester to check amperage all i have is a test light hooked to the negitive side of the battery. i have unpluged the key switch and the light switch. all the fuses are pulled out. it has to be something not going thru the fuse box in guessing.
Thread Starter
Heel & Toe
Joined: Mar 2009
Posts: 19
Likes: 0
From: Broken Arrow Ok.
got the alternator checked it was ok. left it un hooked and trying to hook everything else back up to see what happens. found some wires tape together some one has spliced got a stymatic hope it is right.
