How do I re-charge THIS battery... - PeachParts Mercedes-Benz Forum

MercFan · #1 11-22-2009, 04:51 PM

I left my key turned in the ignition for several hours yesterday, so I wanted to charge up the battery a little, but when I examined the battery a bit closer I noticed that it's probably not a maintenance free battery that I thought it was - see the cap in the photo that I have removed... Last time I saw a battery like that was back in Europe 25 years ago where I used to live.

So the question is: should I remove the battery out of the car and place it in a dry spot outside, then pop all the caps off and THEN hook it up to the charger? I remember way back when my dad was recharging a battery like that the acid in it was boiling pretty vigorously...

Thanks in advance -
James

Shawn T. W. · #2 11-22-2009, 07:20 PM

You could get some spillage . . . so I'd remove it, and set it on a piece of cardboard to catch/absorb the leaks, and if your low on "water" only fill it to the bottom of the tubes . . . until after it is charged.

If it still starts the car, I'd just let the alt charge it on the next drive, if it will be soon.

jkubica · #3 11-22-2009, 07:42 PM

Quote:

Originally Posted by MercFan

I left my key turned in the ignition for several hours yesterday, so I wanted to charge up the battery a little, but when I examined the battery a bit closer I noticed that it's probably not a maintenance free battery that I thought it was - see the cap in the photo that I have removed... Last time I saw a battery like that was back in Europe 25 years ago where I used to live.

So the question is: should I remove the battery out of the car and place it in a dry spot outside, then pop all the caps off and THEN hook it up to the charger? I remember way back when my dad was recharging a battery like that the acid in it was boiling pretty vigorously...

Thanks in advance -
James

Hi
Should be no need to remove the battery if you use a slow charger like 10 amps. Take the caps off to check if the acid levels are where they should be and observe the bubbles in each cell while charging - all cells should bubble at about the same rate. Better yet, get a hydrometer at the parts store and check the specific gravity of each cell - all the cells should be close to the same. If the above tests show a big differance between cells, the battery is defective

The bubbles are hydrogen gas which will explode with a spark - so don't connect or disconnect the charger leads with the caps off.

That said, just leaving key on for a few hours shouldn't drain the battery. If it will still start, just let the alternator charge it while driving.

Good Luck,
Joseph

pawoSD · #4 11-23-2009, 12:30 AM

The key turned in the ignition uses hardly any power, just some juice to activate the gauges and climate control....and a couple teeny lights....that's it. Just fire up the car and let it run for 10 minutes, that will charge it right back up.

babyjames · #5 11-23-2009, 12:36 AM

If you do decide to "top off" the cells, be sure to use only distilled water. I'm in agreement r.e. not wasting too much time charging the car. If it starts, well, why worry? Alternator bad?

For charging in situ, trickle. 2 amps, and keep an eye on the meter.

Jay.

MercFan · #6 11-24-2009, 11:52 PM

Well, I've been having a bit of bad luck lately - got in the car today to try to initiate the starting procedure after I've drained the tank, hoses, changed filters, etc... turned the key and.... the engine turned over twice (just barely) and then it would not turn over again... the battery is dead. My leaving the key in the ingnition for several hours must have drained it - and the battery is an original one too so it may not have been the strongest.

I removed it from the car (just in case), placed it outside, removed the caps and set the charger on a slow 2A recharge overnight - hopefully I can bring it back.

Here is the puzzler: since I have another Benz I thought: why not hook up the battery from my 300D to start my SDL - I started my 300, hooked up the jumper cables to the SLD, I revved it up so the RPM stayed higher and tried to start the SDL.... same d&^n thing: it would only turn over once or twice and that's it!!! Why is that? My 300D has a strong fresh battery - does the SDL require a much bigger battery than that to turn over? I was surprised and confused at that - what's up?

Attaching the photo I forgot to attach in my original post.

#7 11-24-2009, 11:55 PM

Sometimes you're limited by the capacity of the jumper cables; if the battery is dead all the current has to pass through those cables.

Do you know the year of that battery?

pawoSD · #8 11-25-2009, 12:02 AM

That battery looks just like mine, and mine is not even 3 years old.....I highly doubt it is the "original" battery.....it is an OEM battery, but not the one that came with the car.

Yours may be several years old, in which case it might be at its end....

MercFan · #9 11-25-2009, 12:05 AM

Quote:

Originally Posted by Craig

Sometimes you're limited by the capacity of the jumper cables; if the battery is dead all the current has to pass through those cables.
Do you know the year of that battery?

Yeah, the cables sure got warm in just few cranks... I just checked - there is no indication what year the battery is - it's not on top or on any of the side labels...

I didn't see any indication in the receipts when the battery was replaced, it's either original or the receipt was not kept - though the records appear to be in good order on the car.

At any rate - I hope that I can recharge it overnight and then some and it will work tomorrow. If not, I probably would like to get an Interstate battery, if I can find one. If not - probably another Group 49 battery (1000 CCA)?!

pawoSD · #10 11-25-2009, 12:51 AM

My parts car has a pretty new Interstate Battery in it, the biggest one. Its for sale, but I don't think it'd be cost effective shipping it to CO.

MercFan · #11 11-25-2009, 01:00 AM

Quote:

Originally Posted by jkubica

Better yet, get a hydrometer at the parts store and check the specific gravity of each cell - all the cells should be close to the same. If the above tests show a big differance between cells, the battery is defective

BTW - what is a hydrometer - and what does it measure?! Water to acid ratio in each cell!? Maybe it would be worth it for me to try to 'cook' the battery before I junk it - hate to discard a battery that looks practically brand new.

compress ignite · #12 11-25-2009, 04:07 AM

"A hydrometer is a device for measuring the specific gravity of a liquid relative to water, which is assumed to have a specific gravity of 1.00000."

With the correct liquid level in the battery,it may take more than overnight @ 2 Amps.

'Had a set of Marine outboard batteries that some one had let sit all winter,hooked up, in the boat...Tested BAD... 72 hours later @ 2 Amps
they LOAD tested GOOD and the Specific Gravity tested O.K. Too.
(I'm assured their Lifespan was substantially shortened as a result of the Total Disharge.)

jkubica · #13 11-25-2009, 08:47 AM

Quote:

Originally Posted by MercFan

Yeah, the cables sure got warm in just few cranks... I just checked - there is no indication what year the battery is - it's not on top or on any of the side labels...

I didn't see any indication in the receipts when the battery was replaced, it's either original or the receipt was not kept - though the records appear to be in good order on the car.

At any rate - I hope that I can recharge it overnight and then some and it will work tomorrow. If not, I probably would like to get an Interstate battery, if I can find one. If not - probably another Group 49 battery (1000 CCA)?!

Hi
I just bought a Group 49 MAXX battery from Wal-Mart for $75. Interstate is also good - my last one lasted 7 years. As you likely know, the little paper round code stickers that they date batteries with - the first letter is the month and the number is the last didgit of the year.
Joseph

mplafleur · #14 11-25-2009, 09:17 AM

It's not uncommon for group 49 batteries to have the caps on the cells. Being sealed however doesn't mean you won't get spillage from a charge.

I took out and charged my sealed group 49 Die Hard two nights ago and noticed last night that it was sitting in a huge puddle of battery acid. I wiped it up with an old towel (that will soon dissolve into lint). The epoxy garage floor is now very clean in that spot now.

As for jumping with cables, you only get a partial connection through the jumper cables. To really work well, you need to clamp on cables from battery to battery, which isn't very practicable.

JHZR2 · #15 11-25-2009, 10:14 AM

Quote:

Originally Posted by MercFan

I removed it from the car (just in case), placed it outside, removed the caps and set the charger on a slow 2A recharge overnight - hopefully I can bring it back.

Here is the puzzler: since I have another Benz I thought: why not hook up the battery from my 300D to start my SDL - I started my 300, hooked up the jumper cables to the SLD, I revved it up so the RPM stayed higher and tried to start the SDL.... same d&^n thing: it would only turn over once or twice and that's it!!! Why is that? My 300D has a strong fresh battery - does the SDL require a much bigger battery than that to turn over? I was surprised and confused at that - what's up?

Attaching the photo I forgot to attach in my original post.

So you hooked up a battery from another car to just empty battery cables? I don't think that is good, as the battery needs to absorb ripple from the alternator. Even if you had a shorted cell or something, it is important for the battery to be there.

Sounds like you didnt have a good connection. It takes a LOT of 12V current to start a diesel...