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Then fully charge the battery, and then disconnect the neg battery cable. Then put the Digital meter in current measuring mode and connect one lead from to the neg terminal of the battery and the other lead to the disconnected batt lead. This will allow you to measure the current draw with the car just sitting there (sometimes called the static current draw). Now - it's not uncommon for certain computers in the later C4's to wake up as power is restored - so wait 5 minutes for the to "go back to sleep" before noting the current flow.
I can't speak for all C4's - but the LT1 cars typically pull between 20mA and 50mA when sitting.
This popped up on my YouTube feed last night. I watched it after remembering your problem. The video is basically a step by step of what "Purple 92" suggested.
The battery tender seems to really extend the life of batteries for me. I have a factory battery in my 2011 M3 and it's still hanging in there even with the FL heat. If you opt to not use one you likely aren't getting more than 4-5 years out of a battery.
It has been my experience that batteries nowdays are not built as tough as they uses to be. Batteries used to last 5 to 7 years, however in my experience most newer batteries last more like 3 to 5 years. Especially on cars that do not get driven a lot, and don't do a lot of long distance driving.
I just today had to replace the battery on my truck, which is my DD. It was 3.5 years old, and even fully charged didn't have enough amps to crank the engine.
It has been my experience that batteries nowdays are not built as tough as they uses to be. Batteries used to last 5 to 7 years, however in my experience most newer batteries last more like 3 to 5 years. Especially on cars that do not get driven a lot, and don't do a lot of long distance driving.
I just today had to replace the battery on my truck, which is my DD. It was 3.5 years old, and even fully charged didn't have enough amps to crank the engine.
This has been my experience as well. Despite advances in battery technology, the lifespan of automotive batteries seems to be shorter, and they rarely give much warning that they are failing.
Especially here in South TX, where high average temperatures tend to evaporate the electrolyte faster, I typically replace the battery with warranty remaining. Sometimes I'll replace one prophylactically...
Since I use the C4 only once or twice a month, I do keep it on the battery maintainer/desulfator.
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Originally Posted by NavAir
This has been my experience as well. Despite advances in battery technology, the lifespan of automotive batteries seems to be shorter, and they rarely give much warning that they are failing.
Especially here in South TX, where high average temperatures tend to evaporate the electrolyte faster, I typically replace the battery with warranty remaining. Sometimes I'll replace one prophylactically...
Since I use the C4 only once or twice a month, I do keep it on the battery maintainer/desulfator.
Steve
I have to wonder if it's that the manufacturers won't (vs can't) present batteries with the longevity of old. If (for all/most) levels of quality, they actually present the SAME, low-level battery, the difference becomes the warranty. You pay more to get a better warranty.
In doing so, they "lock" you into purchasing THEIR batteries indefinitely. That's because you are under the perception you are getting something...in the form of a partial payment when it's time to get the next battery. And, the cycle continues. If you go somewhere else, you've lost that PREPAID partial payment toward the new battery (which, of course, was in the perception of buying a better battery a couple years ago).
Of course, I can't prove it, but it makes a lot of sense from the manufacturer's viewpoint. Why NOT keep you coming back by hooking you with a warranty...while pushing entry-level (cheaply-made) products that keep you paying more in the future?
And...you heard it here first...from the fair and honest Corvette Forum website!
Thanks to all for the information. Definitely time for a new battery.
I was just curious about the effect the Battery Tender (brand name) had long term on the battery? is it as good as driving the car just about every day? is it better??? worse ? I know its better than not having it on a car thats not driven regularly...Jusy food for thought I guess ...thnks again to all
Just replaced my battery in my '93. I usually try and start it 4 or 5 times in the winter but did not this year. It seemed like I had to jump it about everytime I wanted to use it.
I did add a shutoff switch to it to disconnect it during the winter months.
Last edited by scotth48; 08-25-2017 at 02:06 AM.
Reason: Missing word
I read this post and it has been most fun! I spent years testing batteries and am a bit familiar with the subject. I discharged batteries to verify capacity and then recharged them. It was interesting work IF you like batteries.
First, buy a charger that is designed for the type of battery that is in your car.
If you have one of the OPTIMA "Spiral" batteries be warned. You should not charge it with any typical charger. Optima makes their own chargers for these batteries. The one I have has a small 12 volt battery in between the charger and the Optima battery.
If you have a typical Flooded Lead Acid (FLA) battery like the auto industry has used for over a century then you can buy a typical charger. Be sure to buy one with the ability to monitor the voltage and turn on and off as needed.
Now they are selling batteries that are called Absorbed Glass Mat (AGM) batteries. This type of battery can survive with typical car charging systems but it would last longer in other applications. This technology is okay but not my first choice for vehicles. I have an AGM battery in my camper for starting and ignition and it seems to be working out okay. I bought it because they have a very low self discharge rate and that is good on Camper and RV's that don't get used very often.
If you use a typical charger designed for FLA batteries on the AGM battery it could cause it over charge and pop it's safety vent. If one of these batteries pops it safety vent they can loose capacity as they can vent the electrolyte out. They should never pop their vent in a perfect world.
If you are using a lead Calcium battery then somebody sold you the wrong kind of battery for starting and ignition applications. These are best used for UPS applications and other storage uses.
I have had bad experiences with the Harbor Freight chargers, one I had put out 750 m/a continuously 24/7 and it cooked a brand new Interstate $150+ battery in one winter season.
Battery warranties are a JOKE! Do NOT buy a battery based on the warranty. Like mentioned before they are a "Sales Gimmick" and not to be trusted. Kind of reminds me about the "Maintenance Free Batteries" you see today. A huge percent of Maintenance Free batteries are standard FLA batteries that do not allow you to top off the electrolyte which insure that you will be back to buy another battery soon. I still prefer a FLA with an accessible electrolyte reservoir which can be serviced. If the FLA battery's self discharge rate is too high for you then you can try an alternate like the AGM battery.
When buying a trickle charger you need to buy a "quality" one. Be wary of trusting any name brand because that does not automatically mean that you are getting a good charger. I look at the features and how they charge your battery.
The typical cheap units are "Float chargers" and they are okay on big capacity batteries as they will charge continuously and that won't hurt a 500 Amp hour battery, but it will cook your car battery of between 75-100 amp hours (typical).
People are too often thrifty when they buy battery tenders. This is a place to do your homework. I have also seen battery chargers that ask what type of battery it is, they have specific set-points for each individual type, sometimes they work and sometimes they don't. The best charger is the one that was designed for your battery type. Getting one that monitors the temperature is a great feature as it will help protect the battery even more.
Since I don't drive my Corvettes in the winter I put both of the batteries in my heated garage and charge them with a device I bought from Amazon.
"TekPower TP3010HB Adjustable Switching DC Power Supply 30V 10A With USB Port".
You can see it here:
This device is a great little power supply and it has a specialized program just for charging batteries. I have used it and was able to recover lost capacity in my camper's "House Batteries" with it's built in charging abilities.
I have seen some battery chargers that will go close to 16 volts in an attempt to get a FLA battery to get the electrolyte to start to Gas (bubble). I have seen the batteries they were designed for and they are not used in cars. These chargers should not be used in most (starting and Ignition) batteries used today. They would destroy most of the alternatives out there for us like a Spiral or even a AGM battery. The higher voltages work on FLA batteries with certain chemical compositions of the plates. The compounds used to make the plates harder and shed less lead will sometimes need the higher voltages to get to 100% SOC.
I had a battery tender hooked up to the battery when I was adjusting the windows for new weatherstrips. It was an all day thing of rolling the windows up and down checking the water seal all around the window. Pain in the butt. And so I put the battery tender on while I was doing that to keep from draining the battery too low, then let the tender sit on it after I was done until I got the solid green light indicated the battery was fully charged up.
Seems like these batteries have gotten real expensive. I believe I used to could get a 2 year rated battery for around $50 or so. Now, they are around $150.
Batteries are costing more, this is a fact of life.
Part of the reason of this is the cost of reclaiming the raw materials after the user is done with the batteries. Lead has to be recycled and have the impurities removed. This recycling cost is now being built into several types of batteries. The battery companies want us to "share" in these costs, after all why should they have to spend more recycling the product after "we" use it.
It is critically important that the batteries get recycled as they appear in Dumps way to often. The lead from batteries can leach it's way into the water supply and this has been happening too often where they don't recycle.
People in other non-developed countries simply throw them (car batteries) out with their trash. A lot of them have been thrown away near or in waterways. The health effects are staggering in some of these countries.
I have worked for Westinghouse and we built centralized Village Hybrid Power systems where we used very large commercial Storage batteries. Other companies try to get power to the people by giving them a car sized battery, a controller and a PV module making a small system of their own. I saw batteries literally on the banks of the creek (their water supply) outside of one of the villages I did in South America.
With batteries being recycled like they are many components can re-used. Unfortunately they want us to pay for the privilege of using one.
The best way to keep your Corvette battery charged is to DRIVE that Corvette every chance you can! Good Luck!
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I have a top of the line battery charger from Bosch, but only use it I don't use the Vettes which is extremely rare.
They are great to have especially if you live in a state with 4-6 winter months.
I bought an extra wiring harness for the charger and jerry-rigged it. Now I can connect the charger to the 12V outlet in the C4 and C7, but it works on any hot 12voutlet in any car.
WOW!! A lot of great information. I really like the idea of the cigarette lighter outlet used for charging. This was not a serious problem, just more of a curiosity. Thanks once again to all for your input.
A question to PLRX.. What is the smallest gauge wire I could use to put the male end for the lighter? I was thinking of using an old cell phone charger but those wires are really skinny..
08-22-2017, 10:19 AM
