72 ammeter
06-30-2016, 09:31 AM
#1
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72 ammeter
Just installed new battery in 72 small block. The ammeter shows slightly to the positive of 0 under normal driving with nothing turned on. Should it be dead center? It gos to dead center with the headlights and blower on. Also put a rebuilt alternator on a year ago with internal regulator. Should I be concerned?
06-30-2016, 10:24 AM
#2
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What Voltage do you read at the two battery terminals with the engine running at high idle? If it's in the vicinity of 14.0 Volts and your battery stays charged, I wouldn't worry about the needle indication on the Ammeter.
06-30-2016, 10:39 AM
#3
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It reads 14.8 on high idle and 14.4 at idle.
06-30-2016, 11:54 AM
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06-30-2016, 12:55 PM
#5
based on the OP's other posts he has a 1972 C3 so he is in the wrong forum but to confirm the topic of the regulator it's internal and non-adjustable. Would check the double wire connector on the alternator for partially broken or corroded connection.
06-30-2016, 10:43 PM
#6
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The new battery is fully charged at 12.6 volts before starting the vehicle. Drove for 5 minutes and the amp gage was all the way to the right + side and did not move back to the center. Pulled in drive way and checked voltage at idle (650 RPM) 13.8 volts. Seems to me this is overcharging and the internal regulator is faulty. Does this seem right?
07-01-2016, 08:33 AM
#7
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Something is very, very wrong. The Ammeter should NOT be pegged to the right.
I suggest taking the alternator to a competent auto electric shop and let them figure out what's happening.
I suggest taking the alternator to a competent auto electric shop and let them figure out what's happening.
07-04-2016, 09:19 AM
#8
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Installed rebuilt alternator, the ammeter still does not go back to 0 after being driven for. It is about a third of the way to the plus side. Is this still to much charging to the battery?
07-04-2016, 10:24 AM
#9
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Does it have an internal or external regulator?
Are they any devices on when this happens? Do you have a large amp?
Joe
07-05-2016, 01:50 PM
#10
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I believe I said it was a 72 small block, does sound that like a c1 or c2? Also stated it had internal regulator. No devices on. Was just replaced with a 63 amp alternator.
07-05-2016, 02:05 PM
#11
Drifting
A 72 small block IS NOT A CAR---IT IS AN ENGINE. Don't be a wise guy. Wise guys get no answers. If it is a 1972 Corvette, then the post belongs in the C3 forum---NOT HERE !!!
Last edited by rongold; 07-05-2016 at 02:08 PM.
07-05-2016, 06:23 PM
#12
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Moving this misplaced thread to C3 Tech.
07-05-2016, 10:21 PM
#13
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The new battery is fully charged at 12.6 volts before starting the vehicle. Drove for 5 minutes and the amp gage was all the way to the right + side and did not move back to the center. Pulled in drive way and checked voltage at idle (650 RPM) 13.8 volts. Seems to me this is overcharging and the internal regulator is faulty. Does this seem right?
Sometimes the gauge gets screwed up and the needle gets "off".
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inca32 (07-05-2016)
07-06-2016, 06:01 AM
#14
The ammeter is measuring the voltage between two different points in the system. A poor connection or degraded cable will effect how it reads.
In my opinion the alternator is probably fine.
In my opinion the alternator is probably fine.
07-06-2016, 01:12 PM
#15
you ignored my earlier suggestion, post #5, to check the two wire plug for a hidden break which will effect regulator performance. When unplugged and a voltmeter is placed between ground and either number 1 or 2 wire in the plug you should get a non-zero reading.
Last edited by MelWff; 07-06-2016 at 01:13 PM.
07-08-2016, 08:28 AM
#16
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Sorry, I did that and got something like 7.5 volts on the black and white wire (#2 terminal). The black wire was like 13.5.