This problem came up a couple of weeks ago. After +/- a month I decided to take my Vette out of the garage for a ride. But that didn't go as easy as before. It didn't crank up the first time I turned the key. The second time I heard only a click. The battery was dead. I gave the Vette a jump from my other car and everything looked just fine. I drove for more than 50 miles with my Vette before I put the Vette back in the garage. A week later I wanted to take the Vette out of the garage but with the same result as the week before. I had to give it a jump from my other car and drove around with it for two days. But the same problem happened a week later again.
The battery is three years old.

My question is: What advise can you people give me to find out what the problem is. And were to check/start first? Check wiring? Can I find out if the battery is still working properly? And how can I check that? And/or what ells do I need to check?

And when I need to buy a new battery what battery will be my best-buy? I would like to keep it as close as possible to original (As I do with my whole Vette). But durability and quality are also important for me. I rather spent a couple of Dollars more to keep it as close as possible to original and with a good quality than buying something that doesn't work and look good either.

 

Believe it or not there really is nothing wrong. There is a slow drain no matter what. If I didn't drive my 78 for maybe two weeks the battery would barely crank.

Fix was an $8 battery shut off switch. If I was parking it for more than a few days, just spin the switch and kill the battery (it goes between the terminal and the battery right inside the rear compartment - takes about 5 minutes to install).

Since doing that, I never had a problem. A three year old battery may not hold a chanrge as long as a newer battery either of course. But, you'd be surprised what that little switch can do.

 

If your battery is three years old and been run down a few times; probably time for a new battery. I just bought an Optima Red Top for my car and also use a cut-off switch. I changed from a **** type to a blade type switch and like that better.

If all else fails you can use a battery tender. I have used one for weeks at a time with zero problems. They use a very small amount of power.

 

78Vette-SA....thanks. Sounds simple.

But to make sure nothing is wrong I want to do some inspection anyway. For example, does anyone know what the maximum drain may be (for a clock and ???)?

 

Interstate batteries have served me well for years. It looks good in my '78 too.

 

he said what i was gonna say, you can check the battery tender out at www.eastwwod.com , and enter battery tender in the search.

 

Battery tender works great. Mine is actually an Autometer brand, but I keep it hooked up all of the time. It uses very little power, but it solved all problems associated with power drain. In addition, it also came with a "solar" connecter (withh a panel you can pout in the window. I have never used thjis feature, but it was an ok feature. I got it at Vic Hubbards in Hayward, CA.. (and no battery problems since)

 

"OHSIXX" and "gr8whte", thanks for your advise for a cut-off switch. Personally I see a cut-off switch as a solution I could use if anything ells can't resolve the problem. I think that, if possible, problems should be resolved there were it starts.

"Timbo79" thanks for your advise for a Battery Tender. I'm going to use your advise. This because I'm not driving, or going to drive, my Vette daily/weekly. Probably once a month or so. As soon as I'm sure there is no abnormal leak current I'm going to use a Battery Tender to keep my battery in good condition and always ready to start the engine. Thanks again.

I'm still looking/ searching for an answer on my question what the normal/maximum/reasonable leak current is. Anyone????

 

The battery can be tested by any competent garage/auto repair shop. My guess is that you have one or more bad cells that preclude a full recharge. When I had my 1979 it could sit for up to six weeks with no problems. But as you can see from the pic I had a disconnect switch.

As to draw I do not know the specs. I can only think of three electrical sinks: clock, burgler alarm and radio pre-sets. Perhaps someone could pull out the factory manual and get the off-ignition draws for those.

As to choice of brand I tend to stay with AC Delco. The battery in the pic is Delco and was purchased eight years ago. It is still in service.

 

I agree with OHSIXX. I have an Optima gel with a battery tender. I had to put a battery in it every year till I went this route. Cars that tend to sit a lot will always have battery problems. I use tenders on all my cars that sit. my 87 Jeep Wrangler, Jet Ski, and my son's 23 T-Bucket.

 

depends on many factors. what accessories you have, ie clock, alarm, stereo with direct bypass to battery to maintain station settings, etc. aside from all this, however, i've had several battery "experts" tell me that you can never stop all leakage if battery pos and neg terminals are connected. and, 2 to 3 per cent drain of total battery charge PER DAY is normal. that means that after a month without driving you've lost at least half you battery's charge. and most vehicles won't start if battery is depleted to that level. also, cranking batteries (like in your car) are not designed for repetitive "deep cycling" ie. repeated depletion and recharging. once depleted significantly they will never recharge completely and it gets worse with each depletion of charge.

best solution is either trickle charger (battery tender) or cutoff switch connected to negative terminal (what i use). one of these two options is a must for anyone who doesn't drive their vehicle at least several times per week (like most C3 owners). otherwise, plan on replacing your battery once or twice a year.

you can take your battery to Autozone (can i say that on the forum?) and they can load test it and tell you the condition of the battery and if it should be replaced.

hope this helps.

 

I totally disagree. My '79 can sit for 2 months and will fire right up with no sign of slow cranking. This is with the original starter, original alternator, and the very cheapest Wal-Mart battery ($29.95).

Gert-Jan needs to pull his battery and take it to AutoZone. They will put it on a discharge tester which will tell him if he has a weak or dead cell in the battery, which is what it sounds like to me.

I had to replace the battery in mine this year. The previous $29.95 Wal-Mart battery lasted 5 years.

 

Thanks for your professional response "Greyghost79".

The first thing I'm going to do now is (as you and "Stoge" advised), to bring the battery to AutoZone to do a discharge test on it.

Will be continued........

 

I have only had problems when the weather gets cold - the batter shut off switch solved my problems.

 

They also sell one for side mounting at AZ.