Is a battery a battery, or do I need a Porsche battery? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Finnegan · 12-30-2019, 06:59 AM

Hi All,

My battery had been showing signs of age, and finally went out over the weekend. I'll take it in and get it checked today. If it needs to be replaced, do I need a particular brand?

Finnegan · 12-30-2019, 07:11 AM

Ah. Thanks, google!

https://sites.google.com/site/mikefocke2/batteries

Troy.Boxster · 12-30-2019, 07:14 AM

I have a Bosch battery with similar specs as OEM and it has served me well. It even took a charge well the other day after I let it run down because I hadn't driven the car for a while and I don't have easy access to exterior power to keep it on my battery tender.

BRAN · 12-30-2019, 07:21 AM

I tried curing some Porsche batteries myself, not worth the hassle and uneasy feelings.
Best investment ever was a trickle charger...ever since, no battery problems anymore.

After two dead Porsche batteries, my weapon of choice is a BOSCH S4, inexpensive and very reliable with a trickle charger.

TeamOxford · 12-30-2019, 10:52 AM

I used to use Bosch batteries. Switched to Interstate because it was the only battery I've ever owned that actually lasted for the advertised duration of the battery. A 72 month battery lasted six years without failure. Pretty impressive considering the climate in Dallas, where temps reach well over 100 degrees in the summer. And sometimes spring and fall.

Of course, I live about ten miles from an Interstate distribution center, so I can buy my batteries direct, with a birth date within a month of purchase.

Just sayin'..........

TO

PaulE · 12-30-2019, 11:22 AM

I had an Interstate 84 month lead acid battery that lasted 10 years and was still going strong but I was getting nervous and felt I got my money's worth, so I just replaced it with a Bosch AGM unit since Pep Boys had it a a great price. My battery is always on the CTEK maintainer whenever my car is parked in the garage, even if I am driving it every day.

Finnegan · 12-30-2019, 12:31 PM

All better. I went with an inexpensive Autozone battery.

I was surprised that the old battery had a vent. I'd never seen that before. The replacement does not. Is that an issue?

Oh, and the time-out fixed my radio, again. So that's nice.

Qingdao · 12-30-2019, 01:35 PM

Quote:

Originally Posted by Finnegan

All better. I went with an inexpensive Autozone battery.

I was surprised that the old battery had a vent. I'd never seen that before. The replacement does not. Is that an issue?

Oh, and the time-out fixed my radio, again. So that's nice.

The vent is for Hydrogen.

Your new battery should have a little orifice that you can attach a hose to that vents the hydrogen out into atmosphere. Its designed for trunk or cab mounted batteries so the gasses from the battery can escape the cabin.

If you don't see a little spot for a tube then you have a vent in the caps on the battery.

Finnegan · 12-30-2019, 04:00 PM

Quote:

Originally Posted by Qingdao

The vent is for Hydrogen.

Your new battery should have a little orifice that you can attach a hose to that vents the hydrogen out into atmosphere. Its designed for trunk or cab mounted batteries so the gasses from the battery can escape the cabin.

If you don't see a little spot for a tube then you have a vent in the caps on the battery.

I looked for just such a port, and found nothing. Is my frunk going to fill with hydrogen and kill me?

Qingdao · 12-30-2019, 05:02 PM

Na, I mean old bugs had batteries under the back seat with venting from the caps.

Then again old bug floor pans are notorious for rust in the battery compartment. (well they rust everywhere, but first in the battery tray)

If it were me I'd get a battery with a proper vent tube. Just to eliminate the corrosive element of natural battery "breathing".

Brian in Tucson · 12-31-2019, 06:31 AM

Quote:

Originally Posted by Qingdao

Na, I mean old bugs had batteries under the back seat with venting from the caps.

Then again old bug floor pans are notorious for rust in the battery compartment. (well they rust everywhere, but first in the battery tray)

If it were me I'd get a battery with a proper vent tube. Just to eliminate the corrosive element of natural battery "breathing".

Yup on the VW battery falling thru the floor. In Michigan, when I was a kid, all my cars seemed to have rusted out floor pans.

I didn't worry about the vent, when the Bosch battery died, I replaced it with a Walmart AGM, no vent. When I store my car (lately all the time) I disconnect the battery and occasionally slap a charger on it.

Brian in Tucson · 12-31-2019, 06:34 AM

Quote:

Originally Posted by Finnegan

I looked for just such a port, and found nothing. Is my frunk going to fill with hydrogen and kill me?

No, and if you're worried about corrosion under the battery, go to a marine supply and get a pint of zinc chromate and coat the battery tray. Back in the day, I had a Fiero with a swiss cheeze battery tray, I replace it of course. What a crappy car!

tommy583 · 12-31-2019, 07:33 AM

I just got an Autozone battery. There are 2 vent holes. One on each side. You cap off the side you're not using with the cut out circle on the red cover. The problem I'm having is the vent hole is totally different than the setup on the Interstate battery I took out. I'll have to get some kind of adapter to make it work.

mikefocke · 12-31-2019, 10:29 AM

The 986 (Model years 1997-2004) takes a BCI Group 48 (12.1X 6.9 X 7.6"), the 987 (2005-) takes a BCI Group 94R ( 12.4 X 6.9 X 7.5 "); both right hand positive terminal. The 94R is also slightly lower in CCA.

The 986 Tiptronic battery is bigger than the manual transmission version. They are listed this way in the general section of the official repair manuals:
Ah/A 60/280 Manual
Ah/A 70/320 Tiptronic
So buy a bigger CCA battery if you live in colder climes, drive a TIP Boxster, or have a bigger amp in the car.

Qingdao · 12-31-2019, 01:56 PM

Quote:

Originally Posted by tommy583

I just got an Autozone battery. There are 2 vent holes. One on each side. You cap off the side you're not using with the cut out circle on the red cover. The problem I'm having is the vent hole is totally different than the setup on the Interstate battery I took out. I'll have to get some kind of adapter to make it work.

A bit of rubber hose will adapt it just right.

It doesn't have any pressure its just were the battery breaths.

Glass mat batteries don't breath, so they don't have vent holes in either the caps (which they don't have) or through a little "spout".

Finnegan · 01-02-2020, 07:48 AM

Well, sure enough I found the two tiny vent holes on the battery. They are totally incompatible with the vent hose in the frunk. I guess now I need to go find an adapter? Oh, and the plug for the other side.

Nine8Six · 01-02-2020, 07:57 AM

Just let it breath on the passenger side of the battery, next to that cabin filter you know, a lil air mix a sulfur trioxide won't kill anyone

Now that you guys mentioned, I'll head over the frunk myself and double-check that this new battery they installed for me last year was in fact installed properly :/ Good call...

tommy583 · 01-02-2020, 08:04 AM

Quote:

Originally Posted by Finnegan

Well, sure enough I found the two tiny vent holes on the battery. They are totally incompatible with the vent hose in the frunk. I guess now I need to go find an adapter? Oh, and the plug for the other side.

The plug is on the red cover, unless you threw the cover out

Finnegan · 01-02-2020, 09:51 AM

Quote:

Originally Posted by tommy583

The plug is on the red cover, unless you threw the cover out

lol. Of course I threw it out. After the guy installing the battery asked his manager and we were both assured that this battery didn't have a vent.