Battery advice

Hi All

Many thanks to all of you who advised me on my previous starting problems, my recon starter motor is fitted and working a treat!

That is until the battery appears to have given up on me (one thing after another!) After trying to charge it a couple of times, it attempts to crank the engine for a second and then dies, after the attempted start the multimeter reads a drop in voltage to about 10v from the initial 12.4v, plus the little inspection light that should be green has given up all together.... I think its dead

Before I rush out and buy another, does anyone have any advice as to what I should get? the one in the car is : cca-680A etn-70(Ah) is this adequate for a 2.7 lux or should I be looking for something a bit stronger?

thanks

Jeremy

Unless you are starting the car regularily in sub zero (F) weather, the stock battery size is fine.

The thing with batteries is people think that if they put a bigger battery on a car, they will get more power. The thing is, unless you upgrade the alternator at the same time you will get little more power than the standard battery.

The standard battery should be an 065, the high spec version would be an 075 calcium. A good battery supplier should be able to midtronic test (or equivalent) the battery prior to sale to show you that it's a good battery from the off. (Volts no lower than 12.60, amps close to cca printed on the battery label.)

Big battery = more cranking power, without changing the alternator. Like i said, you will only notice it in -10,-20,-30 degree (F) weather, when the car doesn't want to turn over easy.

stock battery size should be fine. Keep in mind too that a battery's dead time as it is stored before sale can shorten it's life. Most batteries should have a production date on them. I just replaced the original battery in my 97 wrangler build date 9/96 last month! I have had batteries last typically only about 5 or 6 years. Factory batteries are usually in that catagory. Optima is my first choice, but I have had good luck with Exides and Interstates. I believe the Jeeps "Mopar" batteries are supplied by Interstate. Diehards I have experienced plate failures numerous times.
Good luck.

quote:

ORIGINAL: PorscheDoc

Big battery = more cranking power, without changing the alternator. Like i said, you will only notice it in -10,-20,-30 degree (F) weather, when the car doesn't want to turn over easy.

Yes, initially you would get more cold cranking power, but what I meant was, if there is a problem starting, putting a larger battery on won't solve the problem. The alternator can only charge the battery at a certain rate of amps per hour, so if you've got a much bigger battery fitted the alternator will still only charge it at that rate. For eg; if you leave the car standing for long periods of time then when you come to start it you find the alarm/immobilizer has flattened the battery, fitting a bigger battery won't help the problem. Or if you fit a mega stereo system, or other power zapping electronics, you'll find that you are using more amps than the alternator can put back into the battrey....result, a flat battery.

As long as the new battery has the CCAmps as the original the car should start. If not and the battery isn't faulty, there must be a fault somewhere else, yes?

quote:

ORIGINAL: CTiggerPigglet

quote:

ORIGINAL: PorscheDoc

Big battery = more cranking power, without changing the alternator. Like i said, you will only notice it in -10,-20,-30 degree (F) weather, when the car doesn't want to turn over easy.

Yes, initially you would get more cold cranking power, but what I meant was, if there is a problem starting, putting a larger battery on won't solve the problem. The alternator can only charge the battery at a certain rate of amps per hour, so if you've got a much bigger battery fitted the alternator will still only charge it at that rate. For eg; if you leave the car standing for long periods of time then when you come to start it you find the alarm/immobilizer has flattened the battery, fitting a bigger battery won't help the problem. Or if you fit a mega stereo system, or other power zapping electronics, you'll find that you are using more amps than the alternator can put back into the battrey....result, a flat battery.

As long as the new battery has the CCAmps as the original the car should start. If not and the battery isn't faulty, there must be a fault somewhere else, yes?

Correct