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bad alternator?

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Old Mar 12, 2007 | 09:59 PM
  #1  
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az1966
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Default bad alternator?

over the weekend my volt/amp gauge in the dash started twitching when ever I used my turn signals,,never moves if I use the head lights,wipers, radio,,etc...volts across battery is about 14.75 volts with engine running,,pulled neg battery cable off with engine running and engine still seemed to run ok,,no fuss or muss,,,replaced volt regulator and battery ( warranty covered both),,same thing happening,,car runs ok,,but it seems like the 14 + volts is a little high,,,,last year when this started happening it got so bad that it would kill the engine,,turned out it was the ignition switch that time,,,,any ideas ?

1966 coupe 200 ci motor 3 spd manual tranny alternator is a 61 amper from autozone and it's about 2 years old,,,wiring harness under the dash and turn signal switch are both about 2 years old along with the emerg flasher

thanks again for help / ideas
Old Mar 12, 2007 | 10:03 PM
  #2  
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Default RE: bad alternator?

Sounds like the gauge has a grounding problem. Either fix it or ignore it.
Old Mar 12, 2007 | 11:25 PM
  #3  
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Default RE: bad alternator?

Hi AZ. It sounds like you may have a grounding issue, or an incorrect lamp in one of your turn signals. Is the problem happening with the signal in one direction or both? Something is causing your turn signal(s) to pull too much current from the system.
Old Mar 12, 2007 | 11:37 PM
  #4  
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Default RE: bad alternator?

ORIGINAL: az1966

over the weekend my volt/amp gauge in the dash started twitching when ever I used my turn signals,,never moves if I use the head lights,wipers, radio,,etc...volts across battery is about 14.75 volts with engine running,,pulled neg battery cable off with engine running and engine still seemed to run ok,,no fuss or muss,,,replaced volt regulator and battery ( warranty covered both),,same thing happening,,car runs ok,,but it seems like the 14 + volts is a little high,,,,last year when this started happening it got so bad that it would kill the engine,,turned out it was the ignition switch that time,,,,any ideas ?

1966 coupe 200 ci motor 3 spd manual tranny alternator is a 61 amper from autozone and it's about 2 years old,,,wiring harness under the dash and turn signal switch are both about 2 years old along with the emerg flasher

thanks again for help / ideas

ill bet the alt is toast now that is a very good way to kill it!!
Old Mar 12, 2007 | 11:39 PM
  #5  
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mustanglover66
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Default RE: bad alternator?

and 14 volts is a good alt. thats right where it should be.
Old Mar 13, 2007 | 12:41 AM
  #6  
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Default RE: bad alternator?

Well I had a battery that died on me. Well replaced it and the next one died on me. Well crap I though replace the alt time. Well instead I spent five bucks and restripped the wires on the alt and presto no more draining.
Old Mar 13, 2007 | 12:41 AM
  #7  
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az1966
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Default RE: bad alternator?

guage swings in both directions,,,(( NO PUN INTENDED)),,,bulbs have been in ther for a couple years with no problem,,,any way to check the alternater ?
Old Mar 13, 2007 | 12:49 AM
  #8  
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mustanglover66
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Default RE: bad alternator?

you can take it off and take it to autozone and they can test it for you or drive the car there and they can test it on the car along with the starter and battery. I think the instore test is a better one though. I think advance can do the same thing but I'm not shore about that.
Old Mar 13, 2007 | 01:04 AM
  #9  
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Default RE: bad alternator?

I know that we are all used to the 12 volt battery, but really elec systems are designed to idealy run at 13.7 volts. If your volt guage is right, even at 14.7 volts you really are not that far out of range.

Some of the alternators I work with are adjustable, and I often turn these up to about 14.5 volts as this improves battery life.

The only real issue might be electronic items like radios' etc., but if my memory serves me right the last one I installed had an uppervoltage rangeof 15 volts.
Old Mar 13, 2007 | 09:01 AM
  #10  
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Default RE: bad alternator?

I had a similar issue with my turn signals ,turned out to bea bad wire on the socket of the left front turn signal
Jeff



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