Charging system
Thread Starter
Intermediate
Joined: Apr 2007
Posts: 43
Likes: 0
From: Granada Hills CA
Charging system
I have a 67 with a stock 300HP engine. The battery seems to go down significantly after a couple weeks of driving. This has happened to two different batteries that I have put in the car.
I changed the amp meter to a volt gauge and noticed that after starting the car, the volt meter shows charging at about 13.6 volts. However, after a few minutes of running the volts drop off to 11.5 to 12.0 volts.
It seems to me that it should always have at least 13.5 volts. Am I wrong? If not, how do I isolate the issue to either the alternator or voltage regulator?
I would like to get this straightned out before my brother and I drive the car from Southern California to Bowling Green at the end of this May to pick up his new 'vert. Maybe we'll run into some of you along the way!
Thanks, Dan
I changed the amp meter to a volt gauge and noticed that after starting the car, the volt meter shows charging at about 13.6 volts. However, after a few minutes of running the volts drop off to 11.5 to 12.0 volts.
It seems to me that it should always have at least 13.5 volts. Am I wrong? If not, how do I isolate the issue to either the alternator or voltage regulator?
I would like to get this straightned out before my brother and I drive the car from Southern California to Bowling Green at the end of this May to pick up his new 'vert. Maybe we'll run into some of you along the way!
Thanks, Dan
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
I have a 67 with a stock 300HP engine. The battery seems to go down significantly after a couple weeks of driving. This has happened to two different batteries that I have put in the car.
I changed the amp meter to a volt gauge and noticed that after starting the car, the volt meter shows charging at about 13.6 volts. However, after a few minutes of running the volts drop off to 11.5 to 12.0 volts.
It seems to me that it should always have at least 13.5 volts. Am I wrong? If not, how do I isolate the issue to either the alternator or voltage regulator?
I would like to get this straightned out before my brother and I drive the car from Southern California to Bowling Green at the end of this May to pick up his new 'vert. Maybe we'll run into some of you along the way!
Thanks, Dan
I changed the amp meter to a volt gauge and noticed that after starting the car, the volt meter shows charging at about 13.6 volts. However, after a few minutes of running the volts drop off to 11.5 to 12.0 volts.
It seems to me that it should always have at least 13.5 volts. Am I wrong? If not, how do I isolate the issue to either the alternator or voltage regulator?
I would like to get this straightned out before my brother and I drive the car from Southern California to Bowling Green at the end of this May to pick up his new 'vert. Maybe we'll run into some of you along the way!
Thanks, Dan
Safety Car
Joined: Jun 2003
Posts: 3,596
Likes: 8
From: Grosse Ile MI
Alternator/Regulator Explained and Tested
Last edited by stingrayl76; Jan 27, 2008 at 09:01 PM. Reason: Link repaired
Racer
Joined: Jan 2008
Posts: 291
Likes: 17
From: Woodinville Wa
There are all kinds of test .I read Plaidside writeup and it is very good.It sound like you do not have a battery problem.I like to go at problem the simple way first. Check and make sure that your fan belt has enough tension. In my old manual.To tell if it is the alternater or the relay. Turn off all acc. start the car run it to 1500-2000 RPMs' Diconnect the battery it should still run off the alt.Then it should be the regulator.If not it is the alt. Just read from the book.......Good luck... Vince
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
This is done on the car to check the alternator. Pull the alt plug out and identify the "F" field wire connection. Also the large red [wire or post].is easily spotted as the battery hot wire. Run a jumper wire to the field connection from the battery post with the engine running. This full fields the alt and if its ok it will whine and start charging. If it dont the Alt has a problem. This test is identical to a auto parts store checking it on there machine except the machine provides the power instead of the car.....
Le Mans Master
Joined: Apr 2000
Posts: 5,104
Likes: 1,362
From: New York New York
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If stingrayl76 link doesn't work here is another.
http://temp.corvetteforum.net/classi..._Testing.shtml
http://temp.corvetteforum.net/classi..._Testing.shtml
Safety Car
Joined: Jun 2003
Posts: 3,596
Likes: 8
From: Grosse Ile MI
If stingrayl76 link doesn't work here is another.
http://temp.corvetteforum.net/classi..._Testing.shtml
http://temp.corvetteforum.net/classi..._Testing.shtml
Link has been fixed.Dave
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