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W123 car keeps neededing to be jump started.

I recently moved and in Febuary 04 put a brand new battery in, (the old one lasted ~5 years). I only work 1 mile away, and since I'm an American, I drive to work. Actually, I'm a commercial appraiser and sometimes I need to drive around. Anyways, my car, seems to need a good weekly drive, to charge up the battery again, because if I don't get a good long drive, after about a week, my car will not start, and I need to get a jump start. So basically, I'm not driving long enough to charge up the battery? Both belts on the alternator are new as well, and they are tight. So does this mean my alternator is going bad? I'm not like blasting my stereo and A/C on the way to work either. I would just love to try to tackle an alternator replacement, but I'd like to check with you guys first. Thanks.

Darrell

Reply to
Frank Burns
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Check your voltage at the battery when engine is running... you must have at least 13.5 V to charge your battery... if not, then it won't charge your battery.

Repair option? You can try changing the voltage regulator first... very easy job... two screws behind the alternator... and that is it. Otherwise, a rebuilt alternator.

Reply to
Tiger

or your new battery is defective. Check battery voltage.

Reply to
Mr. Elbe

As Tiger said, check the alternator's output voltage and be prepared to change its diodes that regulate the output voltage. They can be bought separately from the alternator. If a replacement alternator IS needed don't waste your time by buying an over the counter brand x rebuilt, buy only a Bosch rebuilt so you do the job only once.

Reply to
T.G. Lambach

The manufacturing date of the car has not been mentioned.

If it came with an ordinary lead/acid battery then a 13.5 volt regulator will fully charge it. If the battery was replaced with a so called "maintenance free battery" it will never fully charge as they require a charging voltage of a least

14.3; preferably 14.8.

My guess with the symptoms presented is that the wrong type of battery has been installed for that particular charging system.

Don't start fiddling with the alternator or it's regulator until the above has been checked out

Joe

Reply to
Joe Bagnara

UNDO THE FRESH CHARGED BATTERY. TAKE THE HOT SIDE A LOOSE FROM THE BATT. GET A 12 VOLT TEST LIGHT AND CLIP THE ALLIGATOR TO THE BATTERY END.STICK THE TEST LIGHT END TO THE HOT POST. IF IT LIGHTS UP ,SOMETHING IS RUNNING IT DOWN. START UNPLUGGING FUSES UNTIL THE TEST LIGHT GOES OUT. OBSERVE THE ANTENNA MOTOR ON THIS FUSE. THEY ARE BAD ABOUT RUNNING THE BATTERY DOWN. ALSO SPIN ALL FUSES AROUND A TIME OR TWO TO MAKE SURE THAT THEY ARE GETTING GOOD CONNECTIONS.

Reply to
RICKY HIGDON

You're shouting when you use caps. Try not to talk so loud. Thanks.

Reply to
L. Cook

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