Alternator output?
Thread Starter
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Joined: Mar 2013
Posts: 72
Likes: 0
From: New York
Alternator output?
Hi all,
On my 81, Whenever I use the turn signals, the needle on the voltmeter in the dash bounces back and fourth with the clicking of the turn signals. It bounces between 13-14 volts when the turn signals are on. Also when I operate the rear defroster, the low voltage light on the dash next to the voltmeter glows very slightly along with the voltmeter plunging down to 13 volts. Is this normal for these cars, or is my alternator maybe dying? It is the original alternator to the car for sure.
Thanks!
On my 81, Whenever I use the turn signals, the needle on the voltmeter in the dash bounces back and fourth with the clicking of the turn signals. It bounces between 13-14 volts when the turn signals are on. Also when I operate the rear defroster, the low voltage light on the dash next to the voltmeter glows very slightly along with the voltmeter plunging down to 13 volts. Is this normal for these cars, or is my alternator maybe dying? It is the original alternator to the car for sure.
Thanks!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
You definitely have alternator issues...or the wiring at the alternator...or your battery cables at the battery are loose and or corroded.
This is a VOLT meter...but your amp output of the alternator may be off or bad.
DUB
This is a VOLT meter...but your amp output of the alternator may be off or bad.
DUB
Thread Starter
Advanced
Joined: Mar 2013
Posts: 72
Likes: 0
From: New York
Thanks for the feedback guys. The battery is new within the last year and all the cables are tight. Ill go down and get the alternator tested one of these days (If it will ever stop freaking raining here). I think its just not putting out enough juice anymore.
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
I had the same problem. Battery about 2 years old. During winter with lights on, heater fan on and turn signal flashing, guage needle would bounce with every flash and voltage would be low until revs were back up. Went from a measly 61 amp to a 105 amp alternator and never a problem anymore.
Pro
Joined: Aug 2013
Posts: 591
Likes: 3
From: Monroe Washington
My 81 definitely has an extra 'pull' on the system when I hit the defroster... Never looked to see if the blinkers would jump that meter though... Did recently replace the batt, haven't used the defroster after that... Will see if that makes any difference after I get the trailing arms back in and start driving her again... Just waiting on the shop to call me to pick em up ...
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