Battery is being drained or just old? - PeachParts Mercedes-Benz Forum

Jason Beal · #1 03-26-2003, 06:12 PM

My battery (240d 1981) was weak so I took it in to be tested. It tested as a good battery, but needed to be charged. When I came to pick it up, the guy was laughing saying that it was driving him crazy because it just took forever to hold a charge. Then we placed a load on it to see how it held out. It was fine. I took it home put it back in the car and it fired right up. Two days later it was dead again. Could there be anything draining this battery on my 240d? The engine stays running when I turn it off and I haven't addressed that yet, but I thought that was vacuum related. Or does it mean it's just time for a new battery and it's on it's last legs?

Thanks for input.

#2 03-26-2003, 06:18 PM

Sounds like a battery in its death throes. It isn't an Exide is it?

84300DT · #3 03-26-2003, 07:21 PM

how about hooking up a voltmeter to see how the alternator is working? just a thought...
car running with the key off is a vacuum issue - nothing to do with the battery.

BoostnBenz · #4 03-26-2003, 08:04 PM

If you suspect a short you can either leave the battery disconnected for a couple days, then hook it up & try it. Or you could use a ammeter to see how much amperage the short is taking.

Agreed, the shut off problem is vacuum not electrical.

#5 03-26-2003, 08:07 PM

I think you might need a new battery, you probally have an internal short in the battery.

Jason Beal · #6 03-26-2003, 08:22 PM

Thanks for the replies. Alt is new so I think it's just time to get a new battery.

BoostnBenz · #7 03-26-2003, 09:04 PM

As Old Deis suggest Exide is frowned upon, Interstate is pretty good generaly, I just bought a Duralast last winter for the 83. Only like $60, about 550CCA + 150CCA reserve with a pretty nice warranty too (3yr? replace), happy with it so far but it'll be a while before the results are official.

#8 03-26-2003, 09:07 PM

Yes, stay away from Excide whatever you do. Some of the older Die Hards are no good either. I am on my second Die Hard, and it seems to be doing very well. They next battery I will buy, will probally come from the dealership

BoostnBenz · #9 03-26-2003, 09:20 PM

Yea I thought about that too, they look pretty impressive. But I found it amusing that it can be bought cheaper with roadside assitance than over the counter at the dealership. Still $110 vs $60, decided to give the cheaper a try.

Jason Beal · #10 03-27-2003, 12:10 AM

I'll have to go look now I'm curious what's under the hood. I'll go shopping this weekend. Thanks everybody.

P.E.Haiges · #11 03-27-2003, 09:18 AM

Jason,

Try Autozone. They have a group 49 battery for $60 with a 7 YR warranty. They put the warranty in their computer so if you lose the warranty papers they will still honor their warranty.

I had a Pep Boys battery that went bad, I man completely dead with acid coming out of one cell. I couldn't find the papers and they wouldn't honor the warranty. Guess how many batteries I'm going to buy from Manny, Moe and Jack.

P E H

BoostnBenz · #12 03-27-2003, 09:38 AM

Autozone sells Duralast btw.

Called a 49-D if I'm not mistaken, specially made for diesels with the added reserve.

Quote:

I couldn't find the papers and they wouldn't honor the warranty.

That is crappy, I thought all the battery stores could go off of the production sticker on the side of the battery, stating month & year.

Jason Beal · #13 03-27-2003, 10:50 AM

I agree about AZ. I have returned items without a receipt and they had it in the computer and didn't give me a problem. It's funny about stores giving you poor service..there are too many other places to spend your money.