battery disconnect issues
Thread Starter
Instructor
Joined: Mar 2009
Posts: 157
Likes: 16
From: Yorktown VA
battery disconnect issues
I have a C3 and C5 vette that dont do much driving in the winter and I decided to install battery disconnect switches onto both of them. I installed the same switch onto both of them just before winter and used the switch to disconnect the batteries this winter. Come this spring, they were both dead and one so dead I had to get it replaced. I have disconnected their batteries negative terminal before through out the winter and have no problem screwing them back in and them starting right up. I used a knife lever style disconnect switch and connected both of them to the respective negative terminal, they seemed like good switches and they seemed to make sense in design... but too much of coincidence that they both died for the first time in year when I put them both on that switch.
Is that a crappy/faulty switch, are those known to be bad or poorly designed switches? or did I mess up the simplest install ever twice in a row?
Because I would love to get disconnect switches for them because I disconnect their batteries more than just in the winter and this would be very helpful. Any tips would be great thanks.
Is that a crappy/faulty switch, are those known to be bad or poorly designed switches? or did I mess up the simplest install ever twice in a row?
Because I would love to get disconnect switches for them because I disconnect their batteries more than just in the winter and this would be very helpful. Any tips would be great thanks.
Race Director
Joined: May 2006
Posts: 18,729
Likes: 2,581
Why would you expect batteries that have gone through a cold winter to still have a charge? You need a battery tender. Look at the Deltran two port unit. They might make it through one winter when brand new but after that highly doubtful.
Last edited by MelWff; Apr 25, 2020 at 08:35 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Agreed. Low temperature is hard on batteries. Over the winter you would do best to have a trickle charger hooked up. A 'smart' charger (raises or lowers amount of charge, as required) is best so that the battery is not OVER-charged unintentionally.
Racer
Joined: Mar 2019
Posts: 327
Likes: 75
From: west mi. / ms. gulf coast
It all depends on how old your batteries are. The knife cut offs should work without any problem. Once you charge up / replace the batteries, check with a voltage meter across the switch to see if any currant is passing through while it is open. That will tell you if your switches are faulty. Most batteries are good for 5-6 years of normal use, less if used less. While cold does have a affect on batteries , I just disconnect both cables on 3 of my stored cars , 8 months later just reconnect and they fire right up. Lat year one didn't , battery was shot [ OLD ] it had volts but no amps. took me awhile to figure that out.
Thread Starter
Instructor
Joined: Mar 2009
Posts: 157
Likes: 16
From: Yorktown VA
Yeah the one battery I've been disconnecting it throughout the winter for over 10 years and haven't had an issue. they are inside so its not terribly cold on them, and great idea checking it with a volt meter. cant believe I didn't think of that.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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i throw a smart charger/ trickle charger on mine through out the winter regardless. Mines inside as well but theres no reason to not keep it fully charged when its so little effort. I have the kind that has bolt on/ plug in connectors so I just open the battery compartment and plug in the charger to it, then plug the charger into the wall. No fiddling with clamps and trying to get a good connection.
But my disconnect is on the positive side and I've added a bypass and a relay so that I can only have the clock and radio memory having power so that I dont have to rest them everytime I kill the power, which is everytime I turn off the key, as a theft deterrent at car shows and fire prevention, just because!
But my disconnect is on the positive side and I've added a bypass and a relay so that I can only have the clock and radio memory having power so that I dont have to rest them everytime I kill the power, which is everytime I turn off the key, as a theft deterrent at car shows and fire prevention, just because!
Last edited by Rescue Rogers; Apr 26, 2020 at 09:00 AM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Its been said, that an automotive type battery looses almost 1% of its charge per day. Well, that's nothing now is it? But wait? It doesn't take a calculator to figure out that after one month, you have lost 30%. And at three months, you have lost 90% of your charge. That's why those batteries on the store shelves are about dead. Somebody has to keep them charged until sold.
Some people put their car batteries in a warm basement in the winter. Not a good idea with furnace, gas hot water heater next to a battery giving off explosives gas.
Both of your "C" cars have parasitic draw. So a shut-off is a must for battery storage life. Like others said, Deltran Battery Tender $25-$40.
There is absolutely no reason to run a trickle charger 24 / 7. Usually a couple hrs a day is sufficient. Rather than constantly unplugging the unit, just get a 24 / 7 wall-outlet timer at Walmart for $7. (Its the kind of timer for turning on a household light) Start out with five charging hrs/day, then 4hrs/day and so on until you tweak it. The cheap timer will add several years the chargers life.
Some people put their car batteries in a warm basement in the winter. Not a good idea with furnace, gas hot water heater next to a battery giving off explosives gas.
Both of your "C" cars have parasitic draw. So a shut-off is a must for battery storage life. Like others said, Deltran Battery Tender $25-$40.
There is absolutely no reason to run a trickle charger 24 / 7. Usually a couple hrs a day is sufficient. Rather than constantly unplugging the unit, just get a 24 / 7 wall-outlet timer at Walmart for $7. (Its the kind of timer for turning on a household light) Start out with five charging hrs/day, then 4hrs/day and so on until you tweak it. The cheap timer will add several years the chargers life.
Last edited by HeadsU.P.; Apr 28, 2020 at 09:45 AM.
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Race Director
Joined: May 2006
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A smart charger senses the current state of the battery and adjusts it's output to bring the battery to a full charge. Once it senses a full charge it goes into maintenance mode. A Deltran for instance has three different charging rates based upon what it senses from the battery.
Burning Brakes
Joined: Oct 2012
Posts: 882
Likes: 52
I do not think you really need the disconnect switch
get Battery Tenders, like these, https://www.batterychargers.com/en/p...ery-maintainer
I use one of these on each of my cars, never had a problem, and I mount the charger inside the batter compartment. They are smart charger, if the battery drops
below 11.7 volts or so, they come on until 12.4 volts or so
you can find them on Amazon for less. New.
get Battery Tenders, like these, https://www.batterychargers.com/en/p...ery-maintainer
I use one of these on each of my cars, never had a problem, and I mount the charger inside the batter compartment. They are smart charger, if the battery drops
below 11.7 volts or so, they come on until 12.4 volts or so
you can find them on Amazon for less. New.
Melting Slicks
Joined: Sep 2004
Posts: 3,225
Likes: 667
From: Northeast
Going on 17 years now, like the OP, I remove the neg cable in late November, put in back on April 1st, start the car and drive home from the storage facility. Hasn't failed me yet.
Now a curiosity question about the tenders. Friend has a tender and with the green light on I tested with a meter, 12.83. Just contacted my brother who uses one and had him check his and with green light on it reads 13.1.
Having a tender not respond until 11.7 and only charge to 12.4 doesn't seem sufficient. Can someone post their reading with the tender on the battery and plugged in. Is there a normal constant when charged and what is that magic number it maintains?
Now a curiosity question about the tenders. Friend has a tender and with the green light on I tested with a meter, 12.83. Just contacted my brother who uses one and had him check his and with green light on it reads 13.1.
Having a tender not respond until 11.7 and only charge to 12.4 doesn't seem sufficient. Can someone post their reading with the tender on the battery and plugged in. Is there a normal constant when charged and what is that magic number it maintains?
Burning Brakes
Joined: Oct 2012
Posts: 882
Likes: 52
I have never bothered to take readings. Every spring the battery is good to go. and the car start. I use it on a 1971 454 and a 1985 L98
never a dead battery starts without issue. There are many on the market, and I may have missed the on/off point. do some research I did 7 years ago. when I got them,
never a dead battery starts without issue. There are many on the market, and I may have missed the on/off point. do some research I did 7 years ago. when I got them,
Race Director
Joined: May 2006
Posts: 18,729
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Going on 17 years now, like the OP, I remove the neg cable in late November, put in back on April 1st, start the car and drive home from the storage facility. Hasn't failed me yet.
Now a curiosity question about the tenders. Friend has a tender and with the green light on I tested with a meter, 12.83. Just contacted my brother who uses one and had him check his and with green light on it reads 13.1.
Having a tender not respond until 11.7 and only charge to 12.4 doesn't seem sufficient. Can someone post their reading with the tender on the battery and plugged in. Is there a normal constant when charged and what is that magic number it maintains?
Now a curiosity question about the tenders. Friend has a tender and with the green light on I tested with a meter, 12.83. Just contacted my brother who uses one and had him check his and with green light on it reads 13.1.
Having a tender not respond until 11.7 and only charge to 12.4 doesn't seem sufficient. Can someone post their reading with the tender on the battery and plugged in. Is there a normal constant when charged and what is that magic number it maintains?
https://www.batterytender.com/site/b...s_OCT_2015.pdf
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Readings of 11.7v, 12.4v, 12.83v or 13.1v is meaningless. Not all voltage meters will read exactly the same. And some batteries are taking a hit from parasitic draw. Even a clock will do that. Or stereo station memory & settings.
Pro
Joined: Nov 2019
Posts: 614
Likes: 56
From: Dover, Delaware
To all thread posters!!!
I am currently using a DelTran Junior automatic battery charger Part# 021-0123 and I keep my 78's battery connected all the time bc it is not a daily driver..
Is this one appropriate for my use??
javajolt78
I am currently using a DelTran Junior automatic battery charger Part# 021-0123 and I keep my 78's battery connected all the time bc it is not a daily driver..
Is this one appropriate for my use??
javajolt78
Melting Slicks
Joined: Jan 2012
Posts: 3,039
Likes: 504
From: myrtle beach sc
Army
The best smart trickle chargers are made by C-Tek. The better units will resurrect a dead battery. I and my daughter have had them do this. I tried using my regular battery charger and it did not work.
I had the C-Tek on the battery for four days on recondition and my battery worked after that. I highly recommend them. Lou.
I had the C-Tek on the battery for four days on recondition and my battery worked after that. I highly recommend them. Lou.
Last edited by loup68; Apr 27, 2020 at 05:13 PM.
Pro
Joined: May 2017
Posts: 583
Likes: 196
From: Wisconsin
I have quite a few Deltran "Battery Tender Plus" model on my cars and motorcycles connected year round that are not driven daily. Been doing that for 20+ years with no problems and long battery life. I got 13 years out of one battery and replaced it just because I was going on a long trip for peace of mind.
.
Last edited by JETS C3-C4; Apr 28, 2020 at 02:33 AM.