Battery Tender...proper answer
Thread Starter
Racer
Joined: Sep 2003
Posts: 469
Likes: 0
Battery Tender...proper answer
I did a search in the archives and cannot find an answer that seems consistent.
What is the proper methodology for hookup if leaving the battery in the car?
Disconnect the battery wires and then hookup the tender to the battery?
or
Disconnect only the negative wire and connect the tender to the battery?
The instructions with my brand of tender says to connect the negative lead to the car frame.......??????
Almost time for storage, so any help is appreciated/
What is the proper methodology for hookup if leaving the battery in the car?
Disconnect the battery wires and then hookup the tender to the battery?
or
Disconnect only the negative wire and connect the tender to the battery?
The instructions with my brand of tender says to connect the negative lead to the car frame.......??????
Almost time for storage, so any help is appreciated/
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
I leave my battery connected when I have my battery tender installed. Most books now say to not connect any cables (jumper or charging) directly to the battery Negative terminal. Some cars even provide separate attaching points for chargers or jumper cables.
A chance of a spark could ignite fumes from the battery. While most batteries are sealed, they still have a vent to let gases escape.
Tenders only provide a small amount of current to the battery so I usually attach the clips directly to the cable's bolt heads. Then I plug the tender in after the cables are attached.
A chance of a spark could ignite fumes from the battery. While most batteries are sealed, they still have a vent to let gases escape.
Tenders only provide a small amount of current to the battery so I usually attach the clips directly to the cable's bolt heads. Then I plug the tender in after the cables are attached.
Race Director
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Originally Posted by c4cruiser
I leave my battery connected when I have my battery tender installed. Most books now say to not connect any cables (jumper or charging) directly to the battery Negative terminal. Some cars even provide separate attaching points for chargers or jumper cables.
A chance of a spark could ignite fumes from the battery. While most batteries are sealed, they still have a vent to let gases escape.
Tenders only provide a small amount of current to the battery so I usually attach the clips directly to the cable's bolt heads. Then I plug the tender in after the cables are attached.
A chance of a spark could ignite fumes from the battery. While most batteries are sealed, they still have a vent to let gases escape.
Tenders only provide a small amount of current to the battery so I usually attach the clips directly to the cable's bolt heads. Then I plug the tender in after the cables are attached.
Been doing the same for 3 winters.
Safety Car
Joined: May 2001
Posts: 4,426
Likes: 0
From: Liberal KS
I use the adapter that hooks up to the battery permanently and just plug it into the Battery Tender every time I put the car in the garage. I've left it on the charger for 1 whole year when the car wasn't running properly until I finally found someone in my area that was willing to pull apart my engine and work on it just recently.
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Brett Foote
Team Owner
Joined: Sep 1999
Posts: 34,062
Likes: 4
From: Evans, GA
I have left the tender connected to a boat battery and the RV battery for several months at a time without any hint of trouble. I always connect directly to the battery except for the 88 Vette that I owned and I used a lighter plug for that connection.
Le Mans Master
Joined: Feb 1999
Posts: 6,470
Likes: 2
From: levittown pa. usa Even a bad day with my `Vette, is better than a good day at work
St. Jude Donor '10
there is no problem leaving these things hooked up permanently. Thats what they are for. After they charge the battery, they go into "float" mode, & do not charge the battery any more until it needs it. I installed one on my `87 because if I leave the doors open for twenty mins. while waxing, & cleaning the car, my battery goes from fully charged, to fully dead. I`ve ruined two alternators, because of the batteries (2) going dead. With the on-board charger, I just plug it in every night, & have had no problems. Sure wish I could find out why the damn courtesy lights, & radio can take the battery from Hero to Zero in twenty mins.
Burning Brakes
Joined: Jan 2003
Posts: 931
Likes: 3
From: Portland OR
Originally Posted by kenv
there is no problem leaving these things hooked up permanently. Thats what they are for. After they charge the battery, they go into "float" mode, & do not charge the battery any more until it needs it. I installed one on my `87 because if I leave the doors open for twenty mins. while waxing, & cleaning the car, my battery goes from fully charged, to fully dead. I`ve ruined two alternators, because of the batteries (2) going dead. With the on-board charger, I just plug it in every night, & have had no problems. Sure wish I could find out why the damn courtesy lights, & radio can take the battery from Hero to Zero in twenty mins.
Instructor
Joined: Aug 2004
Posts: 155
Likes: 0
From: CA
I have had the same issue with my '85. I swapped out the seat belts with the doors open, 20 minutes tops, and the battery was toast. After replacing the battery ( 
)..my float charger is on order and on the way. There are a bunch for $5-10 on ebay.http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT