I'm about to go out and check, but does anyone know off hand if you can add water to the stock battery that came in an '08 C2S?

J

 

Pacific Porsche sent a technician to install the battery this evening..it was all covered under warranty. They give this technician a brand new Cayenne to drive around even on his days off but he goes around and takes care of batteries, resetting of DME, etc. He has a PIWIS with him, I told him he could make a few extra bucks on the side

Dave

 

I just bought a 2007 and the engine seemed to turn over slowly so I took it to the dealer. The Porsche service rep told me that it was not pro rated (you would get a replacement within the 4 year period assuming you drove more than 6000 miles per year) but when they checked the battery they said it was ok. You might double check to ensure if it is pro-rated or not. If not, I also just checked on a larger battery from Odssey. It's just out and is a BCI group 49. It measures 14.84 X 6.88 x 7.48 which I believe will just fit in the battery holder. It is longer (by a couple of inches) than the original battery and weighs 60 lbs. I found the battery in stock at Batteries Plus for $149. It's a gell battery like the Optima but built square like convensional batteries.

ChuckJ

 

Just checked my battery acid level on my '08 997C2S. There are 6 "screws" right on top of the battery. I removed them and peered into each cell with a flashlight. Each cell showed acid over the plates. I wish there was some way to see a "max fill" line on the case of the battery, but none was visible. I'm I correct to assume, no water is needed at this point if the acid level is over the plates?

As my car isn't driven but once every week or two, I've had it on the Porsche battery tender since new. I plan on checking the battery level every 2-3 months from here on out and also venting the trunk before starting.

I also plan on installing an Optima Red Top 34r and a Yellow Dog battery adapter plate when it's time to replace the battery. Hopefully I can get a couple more years out of it without it dying or, worst case, blowing up .

J

 

xXxGhotimanxXx

Go back about 6 post before this one & check out the links on how to check the water levels. You are correct that the level should be above the plates and should reach 1/8" from the bottom of the "sleeve" that the plug screws into. The links have some pictures that will help you. Good luck and keep your cranking amps in top shape.

 

^Awesome. Thanks for pointing that out. According to that info I can add a bit of water to my battery. Thanks again, big help.

J

 

Here's what happened to mine from not checking it and leaving it on the Porsche battery tender........

Battery tender had been unplugged from the cig outlet for at least 1 hour.

I got in....turned the key......and BOOM!

 

When a battery charges, it gives off hydrogen gas. That is why there is the vent tube. A battery can also explode from overcharging, which causes large amounts of hydrogen to be generated. During charging you will be amazed at how much hydrogen is generated and you can see it roil the water. This is one reason to use a low amp battery "maintainer" and not a heavy duty fast battery charger. Even with a low amp battery maintainer doing the charging hydrogen gas is still generated but at a slower rate and the vent tube should release the gas.
When the water level is at the top of the range the acid is weaker and less hydrogen is produced and the volume of the hydrogen is lower due to less space. Lower the water level and more volume is available for the hydrogen gas storage and the acid gets stronger. Stronger acid eats the lead plates faster and this can cause a short to occur. If the short is at the top (dry side) and with a spark, the large volume of hydrogen gas ignites. Then Baby Hindenburg is born.