'57 not charging battery

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Denver T-Bird
Posts: 10
Joined: Sun Jun 24, 2018 11:44 pm

'57 not charging battery

Post by Denver T-Bird » Tue Jul 10, 2018 11:03 pm

I am having trouble getting the battery to charge. I took the generator and voltage regulator to a shop to be tested. The generator was good the regulator tested bad. Replaced the regulator. I tried to polarize the generator by touching the field wire to the battery wire for about 2 seconds (per instructions in the shop manual). When the car is not running, I measured the voltage across the battery at 13 Volts, after starting the engine the voltage drops to 12.7. If I remove the positive cable from the battery when the engine is running it dies. Any suggestions? Thank you for the help.

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paul2748
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Joined: Sun Mar 15, 2009 12:23 am
Location: Northeastern New Jersey

Re: '57 not charging battery

Post by paul2748 » Wed Jul 11, 2018 9:21 pm

Did you check the voltage across the battery at idle? At idle, generators do not put out much over 12 V. Run the engine up to 1500-2000 and check it them. You should get between 13.7 to 14.5
1956 Fiesta Red 312
1954 Ford Victoria 312
1948 Ford Convertible Street Rod 302

Denver T-Bird
Posts: 10
Joined: Sun Jun 24, 2018 11:44 pm

Re: '57 not charging battery

Post by Denver T-Bird » Wed Jul 11, 2018 9:37 pm

The engine was running about 1800 RPMs and only got 12.7V.

voltron
Posts: 26
Joined: Thu May 10, 2018 6:06 am

Re: '57 not charging battery

Post by voltron » Thu Jul 19, 2018 8:15 am

Do you have a ground wire between the generator and voltage regulator?

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