C3 Dave

My 79 is usually stored for winter in my unheated garage. This year I had to replace my battery and alternator. My mechanic blamed my battery tender. Any suggestions?

speedreed8

c-tek mus 4.5. sold online and at interstate battery stores.

resdoggie

Find a knowledgeable mechanic.

jim in oregon

First Q..WHICH BATTERY TENDER-MAINTAINER were you using?
Q2:
On what basis.did your 'mechanic' blame the battery tender?

3rd Q. were your alternator and battery in good condition?..cables etc in good shape?
ANY parasitic current draws in your '79's electrical system?
I use a battery tender JR. on my '78..with a simple attachment that plug into the cigarette lighter and doesn't over-undercharge or damage a thing...& Maintains the battery.I did discover a parasitic current draw B4 that..Was in the stock alarm system..My '78 might sit without running for up to a month..but not all winter here in Oregon.. Jim

mark79,80

I don't see the need for a battery tender. I store three Corvettes, two 1980's and a 1979 from November thru March without a battery tender. The cars have a battery disconnect on the negative terminal. I disconnect the battery and reconnect in the spring. They all will start with no battery charging. As I like the batteries to be fully charged. I hook up a charger before starting, and it takes less than 30 minutes for a 10 amp charger to bring them to full charge after sitting for 5 months.

Duane4238

I just turned in an Interstate battery that wouldn't charge up to a full charge (only 12.60 volts). The guy at Interstate said he'd never seen that style "case" before so he looked it up on his system. He was shocked to see that I purchased the battery in 2003. I told him that I took it in the basement every winter and put it on a battery tender that was also on a timer. It would come on once a day for 8 hours and then shut off. He said I must have done something right because he'd never seen a battery that old that still had enough charge to start the car. Take your battery in the house if you live in an area that gets below freezing most of the winter. I've actually had batteries freeze and crack the case because it got so cold and they weren't being used.
Duane

Scottd

Dont bother with the tender if you will be storing for 4 months or more. They cause more problems than they are worth. Just disconnect the battery. When it comes time to wake it up, put it on a slow charge overnight, it will be ready the next day.

Thats what Ive been doing with my motorcycle and cars for 15 years. Due to NY winters and occasional long term military stints, they get stored from 3 months to a year at a time. (My OEM Harley battery lasted me 8 years, so Im doing something right)

lionelhutz

The odds are very small it will happen to you, but when you see the damage caused by a battery or tender that goes bad during storage you wouldn't use one again. Just disconnect the battery and charge it about once a month for a day or two with a smart charger. Or take it out and store it in your basement and charge it about once a month for a day or two with a smart charger.

mikem350

OldCarBum

I've used battery tenders for years on cars, boats and motorcycles. There are many different models and like everything else, you have to have the right battery tender to do the job you need it to do. Some models only put out about 1.65 amps and won't keep up with cold weather, analog clocks and a high cold cranking amp battery. I keep my Battery Tender (3amp output model) attached to my C3's battery all year. I plug it into a 15 amp protected outlet and I've never had a problem. I used to disconnect the negative side of my battery, and do an occasional charge, but the last time I did that my old analog clock quit running until after I went for a drive and the vibrations started it ticking again. But, I live in Northern California where it may only get down to the mid 40's in my garage in the mid of winter.

sstopczy

I've been doing the same thing on my '79 since 2009 without any starting problems in the spring.

Richard Daugird

I'm the opposite of most of you guys. Though I just got my 'Vette this winter, I have had a '65 Riviera for years and years. The A/C isn't fixed as I just finally replaced the radiator. I don't drive it much in the summer(I consider today to be summer as it is 87 degrees). I have killed a battery or two letting the car sit outside(in the shade)for a month or so. I'm talking 100+ degree weather. While I would not rule out parasitic loss, is that enough heat to murder a dormant battery?

zwede

I use a CTEK battery tender and it works well. I drive my car occasionally year round. But it also sits sometimes and I rarely do longer trips. The CTEK makes sure the battery is always good.

Richard Daugird

Also, do you guys think there is any fire risk leaving a charger(not a tender) set at 2 amps on the car for an extended period of time? We had a really bad fire about 15 years ago at my Dad's, never figured out what caused it, but some speculated it was caused by a battery charger left on.

lionelhutz

Yes. Any charger without some smarts to shut it down is not safe to leave on a battery for long periods of time.

7T1vette

Buy a battery tender that has the capability of charging at ONLY THE LEVEL REQUIRED BY THE BATTERY AT THAT TIME. Cheapo battery chargers only charge at a fixed rate. Once the battery reaches a full charge, continuing to be charged at that "fixed rate" will eventually burn out the battery.

Buy a good quality "variable rate" battery tender and you won't have those problems again.

Richard Daugird

I have the Schumacher SC-1000A-CA. Schumacher sais it's great!(go figure).
http://www.batterychargers.com/sc-1000a-ca/

jim in oregon

Well, I use a DELTRAN battery tender jr..for slow charge, maint on the 12v
lead acid zero maint battery in my '78. a it has 4 different 'status' indicators..and will not overcharge the battery even if left connected all the time.. The battery must have at least 4 volts still present or it isn't gonna charge..and the battery must be good and connections proper.. I do not use it all the time..only when for any reason we will not be driving the car for over a week..I dislike the battery disconnect stuff as the battery access in my '78 is a pita..I use the accessory that allows me to plug the tender into the cigarette lIghter receptacle on the console..Always.plug the tender into the car LAST.
B4 starting always disconnect tender FIRST...
I originally bought it BEFORE I identified and corrected a parasitic current draw down issue.MY battery was new..all cables good, alt-charging system fully functional.
Since then I probably DON'T NEED IT...but I still have it and it works fine with no detrimental affects..Simple..effective...a slow chargeing system if your battery is really down, yet not out..Jim

jim in oregon

yep!..

LongRoadHome

My old '97 motorcycle I bought 5 years ago was on a Battery Tender "Waterproof", only 0.8 Amp, every day until a year ago when I realized the electrolyte seemed to be dropping faster than normal. Found it below the low mark and was already 2nd battery I put in after buying the bike.

Checked those batteries yearly to add distilled water. I thought if I used an electric timer so charger would only be on a couple hours each day might help, that was 2 years ago.
Of course I can't be sure because now the new 3rd battery quit on me without being on that charger and so I tested the motorcycle stator/alternator to find it to be bad now. No way to know what was really causing the trouble, both charger and stator or what. Just know I checked stator about 3 years ago and it was okay.

Point is, I'm going to rethink the way I'm using the "trickle" or maintenance chargers.
I have 4 now, 3 others are Schumacher 1.5 Amp 6/12/auto, and a fairly old higher Amp charger/starter.
Will just use sparingly and not daily, probably once a month for a day from now on. Counter to the idea I started with, which was to leave them plugged in full time when not using the vehicles.

In fact, have a tractor and riding mower in a barn on a property elsewhere that don't get put on chargers unless the batteries are found to need a recharge (mower seldom ever has!). And the batteries last as long as others, besides that old motorcycle!

You might already know, a lead acid battery breaks down if voltage drops below a certain threshold, 10.5 Volts, causing sulfation on the lead plates. So most of all it should be a factor of extreme discharge and recharge that shortens their life time. I believe they can sit unused (if no parasitic drain) for a month or two without worry.