1958 Generator problem
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2nd Gear
Joined: Aug 2005
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1958 Generator problem
My battery keeps running down and I noticed that the battery gauge on the dashboard does not move above the mid-line indicating it is being charged while the car is running. Could my generator be bad (it is the original generator)?
Racer
Joined: Feb 2011
Posts: 299
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From: Troy New York
could be bad I guess ...anywhere you can have it tested locally?
Before I would go into a rebuilt, the generator is a very simple device.... it would be very easy to take it apart and clean the copper strips (light steel wool works fine)....on the armature where the brushes ride and replace the brushes....lightly lubricate the brush holder pivots so they set snuggly on the armature....not much else you can do yourself on it....
just blow it out and clean it real good when you put it back together....
my 59 is the original generator and I have never had to have it rebuilt...
have you had the voltage regulator checked out?? I've replaced that more than once over the life of the car... don;t know who could check that for you but they are cheap enough anyways.... maybe someone else here would be able to tell how to test the voltage regulator
Before I would go into a rebuilt, the generator is a very simple device.... it would be very easy to take it apart and clean the copper strips (light steel wool works fine)....on the armature where the brushes ride and replace the brushes....lightly lubricate the brush holder pivots so they set snuggly on the armature....not much else you can do yourself on it....
just blow it out and clean it real good when you put it back together....
my 59 is the original generator and I have never had to have it rebuilt...
have you had the voltage regulator checked out?? I've replaced that more than once over the life of the car... don;t know who could check that for you but they are cheap enough anyways.... maybe someone else here would be able to tell how to test the voltage regulator
Last edited by BobT59; Jan 2, 2016 at 03:39 PM.
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Sure. Several things could be conspiring, any one or more of which could cause a run down battery. The first thing to do is to confirm proper charging system function. Use a DVM set to DC volts and connect to each battery post, engine running above idle. You want to see around 14 volts (13.8 - 14.2) it will depend on temperature and battery condition but that's the range.
If you have that I suspect a drain from the car or a failing cell in the battery.
If not, verify all battery, generator & ground connections are clean and tight, and belt is tight, you want to full field the generator long enough to take a reading on your meter, again set at DC volts. The full field test bypasses the regulator and commands the generator to run full output. This test is described in your shop manual and will determine whether the trouble in in the generator or regulator. I'd tell you how to do it here but I don't know from here how your car is wired.
All of this may sound complicated but its not at all. You should have no trouble determining in 10 minutes exactly what doesn't work. Always better to diagnose and fix once than to throw parts on and never really know what the problem was.
Dan
Last edited by dplotkin; Jan 2, 2016 at 05:20 PM.
Race Director
Joined: Apr 1999
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From: Beverly Hills/Pine Ridge Florida
The generator might need to be re-polarized, or "re-sparked".
Easiest way is to take a wire and touch the Armature terminal of the generator to the POS post of the battery.
http://fergusontractors.org/fena/wp-...-Generator.pdf
Easiest way is to take a wire and touch the Armature terminal of the generator to the POS post of the battery.
http://fergusontractors.org/fena/wp-...-Generator.pdf
Le Mans Master
Joined: Feb 2012
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From: Western Massachusetts
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The generator might need to be re-polarized, or "re-sparked".
Easiest way is to take a wire and touch the Armature terminal of the generator to the POS post of the battery.
http://fergusontractors.org/fena/wp-...-Generator.pdf
Easiest way is to take a wire and touch the Armature terminal of the generator to the POS post of the battery.
http://fergusontractors.org/fena/wp-...-Generator.pdf
Even so, the quick test above will prove if its the battery, the regulator or the generator. If it turns out to be none of the above, he has a light on somewhere.
Dan
Team Owner
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Army
The generator check out procedures are all covered in the passenger car shop manual for the year of your Corvette. I hope its not the voltage regulator - there are no solid state equivalents and the repros are non-adjustable (although some claim they've found a way to do it).
Le Mans Master
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The generator check out procedures are all covered in the passenger car shop manual for the year of your Corvette. I hope its not the voltage regulator - there are no solid state equivalents and the repros are non-adjustable (although some claim they've found a way to do it).
Its a matter of bending the voltage & current regulator contacts in the appropriate direction, the appropriate amount, at the appropriate ambient and with the battery already appropriately charged, so you are pretty much right, they are pretty much non-adjustable, though generator rebuilders often ask for your regulator too as they "set them up" to charge properly using a carbon pile for a load. Don't know how close they get. My experience has been that replacement regulators tend to over charge.
Dan
Last edited by dplotkin; Jan 3, 2016 at 08:51 AM.
