Battery tender?
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Instructor
Joined: Apr 2007
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Battery tender?
I have a battery tender plus hooked up to my 84. It takes about 7 to 9 hours for the tender to switch to maintenance mode. Is this normal? I have a brand new red to orbital in it. Those of you who have tenders, how long does it take from plugging the tender in to having the tender completely charge the battery?
Team Owner
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From: Fort Knox, KY
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I have a tender from Harbor Freight Tools. But since it's intended to keep a full or partially full battery charged (not recharge one that's completely discharged) mine runs in maintenance mode by design.
Thread Starter
Instructor
Joined: Apr 2007
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The battery has been in for 2 weeks now. I had the tender plugged in since I had the battery. My alternator is charging properly. I wonder why it takes so long to recharge with the tender. My harley takes about 10 to 30 minuts after I plug it back in. once the float mode (green light) comes on it stays on.
Drifting
Joined: Jul 2006
Posts: 1,483
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From: Newark, New Jersey
Maybe the battery is bad and wont hold a charge properly. Have a load test done on the battery. In the meantime disconnect the tender. The car should start on an everyday or once a week basis without a battery tender if the battery and alternator are in good order.And if you dont have a draw elsewhere when the car is off. How many amps is the tender? MIne is a 1.25. If its less, then charging times will be longer.
Pro
Joined: Apr 2000
Posts: 696
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From: Jenkintown PA
Maybe up to an hour, but no more...I have the same charger (Battery Tender Jr Plus). I would contact Battery Tender....or return to vendor and get a replacement.Two additional thoughts...1) sure you have a good connection and 2) could have a possible draw causing the charger to over work????
SAVE THE WAVE
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From: Rolla Missouri
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Maybe the battery is bad and wont hold a charge properly. Have a load test done on the battery. In the meantime disconnect the tender. The car should start on an everyday or once a week basis without a battery tender if the battery and alternator are in good order.And if you dont have a draw elsewhere when the car is off.
If your battery is low enough that it needs to be charged every day, you have an excess draw somewhere.
A battery tender was not made to actually charge up a low battery.
You should be able to let it sit for a week or two at a time and still start right up without issues.
I use a tender on my Harley through the winter, but have never put one on the C4 yet.
Probably should though, because it will sometimes sit for 3 - 4 weeks without being driven. But in over 5 years it has always started right up.
Thread Starter
Instructor
Joined: Apr 2007
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I tested for draw. I have 17 milliamps. I have 2 battery tender plus 1.25 amp tenders. I swap the one from the harley and vice versa and same thing between the 2. After a day out and about it takes 7 to 9 hours to completely recharge. The car starts and runs perfectly. Do you guys use battery tenders on your car? how long does it take to go from charging to maintance mode?
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Team Owner
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From: Cincinnati, Oh USA
The tender is charging the battery up until it goes to float mode. Tenders measure the battery voltage and charge it according to the voltage they measure. Older batteries will not normally charge to the higher voltage of a new battery when in normal use, therefore the tender charges your battery to this higher voltage which takes the 7-9 hours you observe before it goes to float mode. You have nothing to worry about.
I have two vettes, one with a conventional wet battery and one with a gel battery and the older wet battery charges to 12.9 volts quickly, but the gel battery takes days to get there with my Harbor Freight battery maintainer.
I have two vettes, one with a conventional wet battery and one with a gel battery and the older wet battery charges to 12.9 volts quickly, but the gel battery takes days to get there with my Harbor Freight battery maintainer.
Last edited by jfb; Sep 1, 2010 at 10:20 AM.
Thread Starter
Instructor
Joined: Apr 2007
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JFB
Thanks. I called Delran the maker of the battery tender plus and the lady told me exactly what you said. In a nut shell, their maintainers take between 3 to 72 hours to fully charge and switch to maintance mode. I have nothing to worry about.
Thanks. I called Delran the maker of the battery tender plus and the lady told me exactly what you said. In a nut shell, their maintainers take between 3 to 72 hours to fully charge and switch to maintance mode. I have nothing to worry about.
Team Owner
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be careful, one of those cooked my battery and now it collects dust somewhere in my garage.
If your Vette is a garage queen, disconnect the negative.
If your Vette is a garage queen, disconnect the negative.
Advanced
Joined: Jul 2010
Posts: 78
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From: Cape Town
I just use a stock trickle charger on my 86 vette and my 94 Camaro - I have battery disconnect switches on both but doing this makes all the radio/mpg etc settings reset and
it resets the ecu so any "learning" is gone - when I start either car after batt disconnect It seems to be very rich and perfromance is not as good till I have driven 20 miles or so.
it resets the ecu so any "learning" is gone - when I start either car after batt disconnect It seems to be very rich and perfromance is not as good till I have driven 20 miles or so.
Burning Brakes
Joined: Nov 2004
Posts: 897
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From: Land of Whiskey Rebels, PA
I just replaced my battery last week (got 50 mos. out of a 36 mo. battery
). The guy says, "it's all charged up and ready to go". I put it in the car, put my Batter Tender Jr. on it, and 6 HOURS later it's still blinking red (CHARGING). Later that night, I come home from a cruise, put the Tender on it, and the next morning I had the steady green light (CHARGED). Obviously, the salesman LIED to me.
