Zurichgnome

Guys, This is an odd one. The battery installed by the PO was nearing the end of its useful life. I bought a BOSCH-36/96 MO 49-850B, which is the spec Bosch battery for a 2002/996 through many parts sites.

The previous battery was snugly held into place with a metal plate that braced and the corner bottom of the battery. The replacement Bosch is about 2-3 inches longer. It is too long to use the stabilizing bracket yet too short to fill the entire battery platform -- so there is a good 2-inches of play/float for the battery in that space. Presumably not good ... anyone else encounter/fix this issue?

Thanks!

fpb111

I just put a Braille group 48 in my 2003. it was ~1,5 inches shorter than the Interstate that was in there. There are three holes in my plate, one for the group 48, one that fit the interstate, (both of which had captive threaded nuts) and a third one for group 49 (larger) batteries that had no threads.

fpb111

what are the dimensions of this battery?


I used
Braille AGM B7548 battery group 48
BCI Group: [?]Group 48
Length:10.9" (277mm)
Width:6.8" (173mm)
Height (without posts):7.5" (191mm)

http://www.braillebattery.com/index....tteries/b7548#

Zurichgnome

Sounds like we have the same battery platform configuration. Mine must be a Series 49, I think that's what the 49 implies in the Bosch product code. It's 13 3/4 long, It would fit fine if I could use the hole with no threads -- any idea how to stabilize under those conditions? Can't

Rant: Why would they thread the last hole!!

(Added Later) Looking at other web sites, it appears that this size battery is not spec'ed as a proper fit for the 996. Folks who are looking to replace their battery may wish to note this as the BOSCH-36/96 MO 49-850B is the default 2002 996 Bosch battery on the Pep Boys and other web sites/stores that sell this battery. Bummer for me.

fpb111

Isn't there room to slide a nut under the plate from the end? Get a new cabin filter and when you pull the left side perforated plastic cover (one or two torx head screws), to slide the nut in for the battery hold down, you can put the new filter in at the same time. WOW two jobs at once How cool is that?

Almost forgot, the battery slides toward the driver's side under the formed lip of the tray. Then the clamp pushes it home and holds it down. Don't get dirty!

Zurichgnome

Love the idea! And I came up with a few alternative stabilizing solutions -- one of which included the use of seven pieces from my sons Harry Potter LEGO set. How's that for Porsche engineering. Ultimately my options were all just too time consuming or sloppy, so I've decided to try to return the battery. The questionable math and logic of 4 hours of work -- including drilling metal-- to install a simple battery (click/vrooom) seemed out of whack!

Did you get your Braille on-line and are you happy with it? I might go in that direction.

fpb111

You should not have to drill the plate. Slide a nut under the last hole and bolt it down with the stock clamp.

I am very happy with it. I bought it on line from HeelToe Automotive
www.heeltoeauto.com. They did not have one in stock so I waited and Braille built one on 2/2/11 and sent it to me. They are not cheap $208 + shipping.
There are other AGMs that need battery box mods, Optima is one. I wanted plug and play.

That said I wanted an AGM (Absorbed Glass Mat) as I have had excellent performance from them in the past, 8 yrs in my 1970S and 9 yrs in my 1972"RS" track car. Also I put an AGM in my bike in 2001 and still get 13.2 volts and strong starts,1998 BMW R1100RT. I also use battery tenders when they are stored for more than 2 weeks.
I removed a good three year old Interstate that was ok but it is a flooded battery, acid and water sloshing around inside often creates crud on the posts and battery box floor..

The AGM will not leak unless you crack the case. They actually shipped mine on it's side in the box.

function12

You need a group size 48. You bought a group size 49 which is a lot longer. I just went through this myself. The autoparts store showed a group 49 was the right battery. Side by side with my old it was no where close to being that big. Group 48 was a perfect match and CHEAPER!! They must not know it fits a Porsche yet.

Zurichgnome

I sent notes to customer service at two of the sites, so hopefully others here don't get stuck with a 40-pound white elephant. Unfortunately I bought mine at a Pep Boys store while on business in Detroit. I don't get back there often and that's the closest Pep Boys to my house. I'm stuck with it; craigslist here I come.

Chris996

This is my photo of installing a short battery. I flipped and bent the bolt on plate to secure the battery.

fpb111

Chris996
how many threaded holes does your plate have? It looks like you added a 4th hole for the clamp screw with the Optima?

A group 49 will fit and can be used by sliding a nut under the plate and running the bolt through the clamp. it is just a pain. I think a group 49 weighs ~50 lbs.

Chris996

Did not add threaded holes, just reversed the clamp. I did the same on my 2000 996.

fpb111

Chris996,
Then you have 4 holes in your plate? Three threaded and one not threaded? Or is the 4th one threaded also?

What year?

Chris996

Will have to take a look, but the plate is stock.

Detoxx

Recently got a bosch group 49 from pep boys (store indicated that it was the correct battery) but it didn't fit with the preexisting threaded holes due to length, only the one that was not threaded.
FIX - You can use one of the nuts (I believe its a 12) that holds down the battery tray (4 in total) then replace the one you use when time allows.
To install remove the 4 nuts holding the battery tray down and remove tray.
Get a piece of tape and one of the nuts. Tape that nut to the underside of the battery tray hole that the battery hold bolt will pass through. Next reinstall the tray, add the battery, and gently install the bolt and hold down bracket. When tightening the bolt make sure the nut doesn't turn (didn't for me) and tighten securely
When time permits go back to pep boys or other auto store and get a replacement nut