Battery Problem

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ROBERTHOOPS
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Battery Problem

Post by ROBERTHOOPS » Sun Apr 28, 2019 3:27 pm

Late yesterday afternoon, four of us went for a ride in my ’27 Touring. After about 20 miles, we drove into a COE park to see the numerous deer there. I stopped at the gate and as the gate keeper was interested in the car, we started talking. I shut down the engine. It was running on mag. When I tried to restart it on battery, everything was dead. I tried to crank it on both battery and mag.
I tried for about a half hour to figure out what went wrong and finally called Hagerty and got the car flat bedded to our house about 8 miles away. When I got home it still wouldn’t start. I the checked the 7-month old 6-volt battery and it only had 4.7 volts. I charged the battery for around 14 hours until it was fully charged. Then I load tested it and the tester showed that the battery was good. Then the car started easily and ran on mag. The ammeter showed charging at about 3 amps.
I’ve owned this car for over 30 years and never had a problem like this. What could have happened that could cause a battery to completely discharge while running on mag?


jab35
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Re: Battery Problem

Post by jab35 » Sun Apr 28, 2019 3:31 pm

When running on mag, how many amps is the generator charging?

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DanTreace
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Re: Battery Problem

Post by DanTreace » Sun Apr 28, 2019 4:24 pm

Poor or corroded connections at the battery + and - terminals can prevent juice to get from the generator to battery, or the cut-out isn't functioning and the generator can't replenish the battery.
The best way is always the simplest. The attics of the world are cluttered up with complicated failures. Henry Ford
Don’t find fault, find a remedy; anybody can complain. Henry Ford

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Topic author
ROBERTHOOPS
Posts: 15
Joined: Mon Jan 07, 2019 8:47 am
First Name: Robert
Last Name: Hoops
Location: Burton,Texas
MTFCA Number: 15877
Board Member Since: 2005

Re: Battery Problem

Post by ROBERTHOOPS » Mon Apr 29, 2019 8:59 pm

Thanks for your replies but I think that I have figured out the problem.
The battery is about 7 months old. The ammeter showed charging at 3-amps before and after the incident. All the battery and ground connections are good. It has a diode type cutout.
The battery hold-down clamp near the positive battery post was a little loose. We had driven on about a half mile of rough gravel road and I think that the battery jiggled enough to short it out.
The battery seems to holding a charge now but I’ll check it again in about a week.
Thanks again, Robert

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HalSched
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Re: Battery Problem

Post by HalSched » Mon Apr 29, 2019 9:18 pm

Check to see if your generator charge is gettin to the battery ussing a volt/ohlm meter. Check the cable and the battery post. As mentioned, the problem could be corrosion between the battery post and the cable connectors.

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