73 Electrical Question
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From: Mt. Pleasant SC
73 Electrical Question
I'm getting an over volatage (+ 40) on my 73 Coupe. Is there a seperate voltage regulator on the 73 or is that internal to the alternator?
Last edited by c3andc5; Oct 18, 2006 at 05:56 AM.
Intermediate
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From: Tyler TX.
I think you mean amps on your meter. Check the alternator at any auto parts store. The voltage should not exceed 14.5. If it does, it means your regulator is out. The regulator is internal to the alternator. You can buy a rebuild kit that includes the diode bridge, regulator and brushes- some even come with bearings. The basic kit without the bearings costs less than $20 or you can buy a rebuilt alternator.
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From: Mt. Pleasant SC
Originally Posted by Dragonwycke
I think you mean amps on your meter. .
Thanks again,
Chris
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From: New Hill NC
The 73 will have a so called amp meter. It is common for it to indicate a high amp reading if the battery is low and is in good condition. When the engine is first started the alternator socks it to the battery until it is fully charged and then falls back. If your meter falls back after a while to more normal levels there is probably nothing wrong. As suggested you should check the real voltage with a VOM and see what that is. It should be in the 13.5 to 14.5 range.
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From: Mt. Pleasant SC
Originally Posted by wombvette
The 73 will have a so called amp meter. It is common for it to indicate a high amp reading if the battery is low and is in good condition. When the engine is first started the alternator socks it to the battery until it is fully charged and then falls back. If your meter falls back after a while to more normal levels there is probably nothing wrong. As suggested you should check the real voltage with a VOM and see what that is. It should be in the 13.5 to 14.5 range.
Le Mans Master
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From: Boca Raton Florida
Does your gauge say Volts or AMPs? Big difference. If your alternator was actually putting out 40+ volts you would have fried lights, radio, all kind of stuff. You should have an amp meter in that car.
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Originally Posted by c3andc5
Car starts up fine and initial reading is normal. With engine running and when load is put on the alternator, such as air conditioner or heater, meter is nearly pegged to +40 on the voltmeter. At idle (700 rpm) the needle is sporadic on the positive side of the voltmeter.
The sporadic jumps while at idle are also normal.
A +40 amp load from the blower fan sounds too high. What does it read when you put on the headlights instead?
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From: Mt. Pleasant SC
Originally Posted by Mike Ward
'73 has a gauge that measures amps, not volts. If with no load on the system it reads zero or close to zero, then that is normal.
The sporadic jumps while at idle are also normal.
A +40 amp load from the blower fan sounds too high. What does it read when you put on the headlights instead?
The sporadic jumps while at idle are also normal.
A +40 amp load from the blower fan sounds too high. What does it read when you put on the headlights instead?
Headlights also cause the needle to peg out to nearly +40 on the guage. Radio causes only a minor change. Would you agree that the internal regulator in my alt has gone bad or is going bad?
Thanks,
Chris
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From: I can walk to MA
Definitely sounds like alternator is not working properly.
Easy test is to use a digital volt meter ... measure battery voltage
with engine off and running. Shoud be about 12v off and 14.5v running.
If not over 14v while running, something's wrong with alternator.
I would remove and take to a parts store that will test it for you.
If handy at all with tools - I would attempt to rebuild if bad.
If not handy ... trade her in for a new one (if bad).
It could also be your meter ... or perhaps battery is bad.
Easy test is to use a digital volt meter ... measure battery voltage
with engine off and running. Shoud be about 12v off and 14.5v running.
If not over 14v while running, something's wrong with alternator.
I would remove and take to a parts store that will test it for you.
If handy at all with tools - I would attempt to rebuild if bad.
If not handy ... trade her in for a new one (if bad).
It could also be your meter ... or perhaps battery is bad.
Last edited by NHvette; Oct 18, 2006 at 12:53 PM.
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From: Mt. Pleasant SC
Originally Posted by NHvette
Definitely sounds like alternator is not working properly.
Easy test is to use a digital volt meter ... measure battery voltage
with engine off and running. Shoud be about 12v off and 14.5v running.
If not over 14v while running, something's wrong with alternator.
I would remove and take to a parts store that will test it for you.
If handy at all with tools - I would attempt to rebuild if bad.
If not handy ... trade her in for a new one (if bad).
It could also be your meter ... or perhaps battery is bad.
Easy test is to use a digital volt meter ... measure battery voltage
with engine off and running. Shoud be about 12v off and 14.5v running.
If not over 14v while running, something's wrong with alternator.
I would remove and take to a parts store that will test it for you.
If handy at all with tools - I would attempt to rebuild if bad.
If not handy ... trade her in for a new one (if bad).
It could also be your meter ... or perhaps battery is bad.
Thanks