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jtfreels's Avatar
 
Join Date: May 2005
Location: Austin, TX
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Alternator/charging problem 82SC

Friday headed to work in my SC, shortly noticed the tach was erratic, bouncing around, then the radio went dark. I turned around and headed home to switch cars,about 3 miles total trip.
Searching the forums lead me to believe that this is a voltage regulator problem (acting if it was putting out too much voltage, tach would show 4k rpm at idle).
Just now got around to start checking it, first thing I check is the battery voltage, oops 11.58 volts.
So now I'm thinking that the alternator has given up.

I guess it's worth charging the battery so I can start it up and check if the alternator is putting out anything?

Comments or suggestions?

Jay

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Old 08-06-2011, 05:12 PM
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Charge the battery.....clean connections check cables and grounds.
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Old 08-06-2011, 05:18 PM
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Quote:
Originally Posted by jtfreels View Post
Friday headed to work in my SC, shortly noticed the tach was erratic, bouncing around, then the radio went dark. I turned around and headed home to switch cars,about 3 miles total trip.
Searching the forums lead me to believe that this is a voltage regulator problem (acting if it was putting out too much voltage, tach would show 4k rpm at idle).
Just now got around to start checking it, first thing I check is the battery voltage, oops 11.58 volts.
So now I'm thinking that the alternator has given up.

I guess it's worth charging the battery so I can start it up and check if the alternator is putting out anything?

Comments or suggestions?

Jay
You need to measure voltage back there where the alternator be, along with the CDI. Poor front to back electrical connection (Battery posts/connections, intertie at starter solenoid?) and the alternator output can get extremely high in the process of trying to charge a partially disconnected battery.
Old 08-06-2011, 06:09 PM
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"the alternator output can get extremely high in the process of trying to charge a partially disconnected battery"

Not if the regulator is functioning properly!

Over-voltaging the result of a bad regulator (internal) on the '82/'83's with the
junk Valeo/Paris Rhone alternator is very common. Most the time the over-voltaging
is intermittent.
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Old 08-06-2011, 07:00 PM
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I took my 82 to autozone they hoocked up a tester and told me that the diodes checked good . i pulled my alternator and had it rebuilt for 75 bucks. end of story. sounds like voltage regulator is bad, part 20 bucks, while its out have the whole thing rebuilt.
Old 08-06-2011, 07:27 PM
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The alterantor/regulator/battery is an all operate together, synchronous, system. The alternator/regulator will not operate properly absent a good solid connection, plus and minus, to the battery.

Ask someone why you should NEVER disconnect the battery with the engine runnning. A partial disconnect will have the same result it just takes longer.

Old 08-06-2011, 09:20 PM
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