SUPPORT OUR SPONSOR

Go Back   Club Cobra > Club Cobra Tech Areas > Shop Talk

Welcome to Club Cobra!  The World's largest non biased Shelby Cobra related site!

  •  » Representation from nearly all Cobra/Daytona/GT40 manufacturers
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and nearly 1 million posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

Keith Craft Racing
Nevada Classics
MMG Superformance
Main Menu
Nevada Classics
Nevada Classics
MMG Superformance
Advertise at CC
Banner Ad Rates
MMG Superformance
MMG Superformance
MMG Superformance
MMG Superformance
August 2022
S M T W T F S
  1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30 31      

Kirkham Motorsports

Like Tree1Likes
  • 1 Post By DanEC

Reply
 
LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 02-18-2014, 12:29 PM
Archrms's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Aug 2006
Location: Jersey Shore, NJ
Cobra Make, Engine: Superformance SPF#2572, 427 S/O 2X4
Posts: 379
Not Ranked     
Default Battery Tender Issues

I have battery tenders on the Cobra, a 1966 Mustang, and a motorcycle. The tenders have been on the Mustang and motorcycle for years with no issues. Last year I noticed a bad egg smell in the garage one day and traced it to the trunk of the Cobra. The battery was fried. It was the original battery so I figured it had just gone bad.

Got a new battery, and hooked up the tender. A few months later, I noticed the smell again. Drove it to the store where I purchased the battery. It was red hot by the time I got there, where they confirmed that it was fried. They gave me lip about replacing the battery so soon under warranty, and said they would not replace it again.

I threw the battery tender on the Cobra out and hooked up the one that has been on the Mustang. Less than two months later the smell was coming from the trunk of the Cobra again. I have not had it tested, but it is likely fried again.

What could be causing the batteries to be fried one after the other while on the battery tenders? I have used two different battery tenders with the same results. I have replaced the Ammeter with a Voltmeter, which was showing normal voltage before being garaged for the winter.
__________________
Peace through superior firepower...or is it horsepower? Either way, more is always better!

Last edited by Archrms; 02-18-2014 at 12:33 PM..
Reply With Quote
Sponsored Links
Sponsored Links
  #2 (permalink)  
Old 02-18-2014, 01:01 PM
DAVID GAGNARD's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Jan 1999
Location: MARKSVILLE,LA.,,
Posts: 3,235
Not Ranked     
Default

Quote:
Originally Posted by Archrms View Post
I have battery tenders on the Cobra, a 1966 Mustang, and a motorcycle. The tenders have been on the Mustang and motorcycle for years with no issues. Last year I noticed a bad egg smell in the garage one day and traced it to the trunk of the Cobra. The battery was fried. It was the original battery so I figured it had just gone bad.

Got a new battery, and hooked up the tender. A few months later, I noticed the smell again. Drove it to the store where I purchased the battery. It was red hot by the time I got there, where they confirmed that it was fried. They gave me lip about replacing the battery so soon under warranty, and said they would not replace it again.

I threw the battery tender on the Cobra out and hooked up the one that has been on the Mustang. Less than two months later the smell was coming from the trunk of the Cobra again. I have not had it tested, but it is likely fried again.

What could be causing the batteries to be fried one after the other while on the battery tenders? I have used two different battery tenders with the same results. I have replaced the Ammeter with a Voltmeter, which was showing normal voltage before being garaged for the winter.
I'm not an electrician by any stretch, but I always dis-connect the positive cable on my battery if I don't plan on driving the car for more than a couple of weeks and have had no issues with batteries/tenders....had one Optima battery last 7 or 8 years this way....
__________________
DAVID GAGNARD
Reply With Quote
  #3 (permalink)  
Old 02-18-2014, 01:23 PM
xb-60's Avatar
CC Member/Contributor
Visit my Photo Gallery
Gold Star Contributor
 
Join Date: Aug 2009
Location: Adelaide, SA
Cobra Make, Engine: PACE 289FIA 'English' spec.
Posts: 12,390
Not Ranked     
Default

I'm with David on this. I have a quick disconnect on the positive terminal, and batteries now last much longer. The car sometimes sits unused for a few months at a time, but there's plenty of kick in the battery after that time to pump fuel through and start. I periodically think of buying a tender, but each time I talk myself out of it because I wouldn't get any advantage by using one.
Cheers,
Glen
Reply With Quote
  #4 (permalink)  
Old 02-18-2014, 01:48 PM
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Feb 2005
Posts: 651
Not Ranked     
Default

I'm curious as to your root problem. I don't have a suggestion. I have 3 vehicles. Each has a battery minder attached. All aren't connected in the same manner.

a. The Cobra: the positive cable is always switched off when sitting. Same battery for about 7 years.
b. The F350 diesel: it has twin batteries. All cables remain connected. Same batteries for about 3 years.
c. The Mustang: All cables remained connected. Same battery for about 5 years. (sold this car last month)



David

Last edited by 601HP; 02-18-2014 at 01:54 PM..
Reply With Quote
  #5 (permalink)  
Old 02-18-2014, 02:37 PM
joyridin''s Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Feb 2009
Posts: 1,632
Not Ranked     
Default

I have a battery disconnect switch and the car/battery has been sitting 4 years now. I started it in October with no problems. The battery is probably 6-7 years old. My bike sits all Winter in the garage without a tender and the battery is 4 years old now with no problems.

Unless your garage gets below freezing on a regular basis or the car/battery has some type of drain on it, using tenders really doesn't help.
Reply With Quote
  #6 (permalink)  
Old 02-18-2014, 03:21 PM
MOTORHEAD's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Feb 2001
Location: BRADENTON, FL
Cobra Make, Engine: KIRKHAM 427 S/C, SHELBY 427 ALUM. STROKER
Posts: 1,381
Not Ranked     
Default

Get a voltmeter (VOM) across the batt terminals when the tender is hooked up and monitor the voltage periodically.
If less than 12, the charger isn't doing its job. but thats not going to "fry" the battery. look for too high voltage (14 + volts) But the same tender works ok on other vehicle.
Need to check charging voltage. First step to figure out whats going on. If voltage is too high or low, disconnect either cable from batt and re-test with VOM.
First guess is car wiring problem. Don't know the wiring on SPF's, Blas has diagrams if you don't, but the nature of these cars is that strange mods by previous owners is always a possibility !
__________________
"When Injustice becomes Law,
Rebellion becomes Duty." T. Jefferson
Reply With Quote
  #7 (permalink)  
Old 02-18-2014, 05:02 PM
Xack's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Dec 2008
Location: Chester, VA
Cobra Make, Engine: West Coast Dreams
Posts: 192
Not Ranked     
Default

The common item is your wiring. Different tenders, different batteries. Chances are your first battery tender is still good. All else being the same, you should buy a disconnect and switch on the -(Negative). The switch makers suggest you switch your -(Negative) side since your switch at zero volts does not arc when switched on or off. Arcing causes oxidation and burned contacts which shorten the life of your device.

Last edited by Xack; 02-18-2014 at 05:12 PM..
Reply With Quote
  #8 (permalink)  
Old 02-18-2014, 05:09 PM
DanEC's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Apr 2009
Location: Little Rock area, AR
Cobra Make, Engine: ERA Street Roadster #782 with 459 cu in FE KC engine, toploader, 3.31
Posts: 4,330
Not Ranked     
Default

I've read too many horror stories about batteries blowing up - apparently from being left on a battery tenders. I use disconnects on my old cars and the batteries stay charged and batteries last a good long time.
joyridin' likes this.
Reply With Quote
  #9 (permalink)  
Old 02-18-2014, 07:06 PM
Archrms's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Aug 2006
Location: Jersey Shore, NJ
Cobra Make, Engine: Superformance SPF#2572, 427 S/O 2X4
Posts: 379
Not Ranked     
Default

I agree with Xack, in that the common item is the Cobra. However, I had no issues with the battery (the original battery lasted five years) before using the tender on it. After hooking up the tender, it keeps frying batteries every few months. It may be easier to just disconnect the battery as suggested and stop using the tender, as it seems to be causing more problems than it is worth.
__________________
Peace through superior firepower...or is it horsepower? Either way, more is always better!
Reply With Quote
  #10 (permalink)  
Old 02-21-2014, 04:54 PM
CC Member
Visit my Photo Gallery

 
Join Date: Mar 2013
Location: Lewes, DE
Cobra Make, Engine: ERA #448, 1964-427
Posts: 96
Not Ranked     
Default

Archrms, Your battery problem is unusual and a concern. I use a battery tender on my Cobra and 2 other cars without a problem. So, you may want to disconnect both battery cables from the battery and then put the tender on the battery. This isolates the battery from the car. If the battery keeps the charge and does not overcharge and heat up, then, your problem is related to the car to battery relationship and further investigation is necessary. Hope this is helpful.
Reply With Quote
  #11 (permalink)  
Old 02-21-2014, 08:25 PM
CC Member
Visit my Photo Gallery

 
Join Date: May 2003
Location: Hudson Valley NY, NY
Cobra Make, Engine: Backdraft, 302, Tremec 3550. #038
Posts: 863
Not Ranked     
Default

I would look into a "Battery Tender" (that's the name) from Deltran. www.batterytender.com
Its the only one I would use. If you look on their site there is a lot of info about how a battery is charged and what happens when it is hooked up to their charger. More info then I ever knew. A little more expensive but well worth it. I've had mine about 8 years and have charged dozens of batteries with no problems whatsoever. I am currently charging 6 - 6 volt batteries for my golf cart with it. Its the smartest way to go if you are going to keep batteries charged.
__________________
Kids in the backseats cause accidents, accidents in the backseat causes kids ! Good reason to get a Cobra !!!
Reply With Quote
  #12 (permalink)  
Old 02-22-2014, 03:37 AM
Ron61's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Dec 2001
Location: Shasta Lake, CA
Cobra Make, Engine:
Posts: 26,400
Not Ranked     
Post

I have used the Deltran Battery Tenders on 3 cars for years and no problems. I do have my disconnect switch on the Negative side of the battery in the 69 Cobra and I had to replace that battery last summer and it was 14 years old.

awfink55s suggestion of disconnecting the battery completely and seeing if it happens is a good one. If the battery is over charging, then something is causing the tender/charger to try to charge it. Possible a small short somewhere in the cable or something is drawing a little current all the time.

Ron
__________________
Ron 61
Ronnie Widener


View my Miscellaneous Gallery
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 02:36 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: CC Policy