Jump to content

The RennTech.org community is Member supported!  Please consider an ANNUAL donation to help keep this site operating.
Click here to Donate

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Open trunk without battery while installing Optima


Recommended Posts

The other weekend I finally got around to installing an Optima battery to replace the original 5 1/2 year old Porsche battery in our '05 997. I made a simple mounting base for the Optima 34R from 3/8" thick HDPE sheet. I plugged my CTEK 7000 battery maintainer in to the cigarette lighter socket hoping to maintain radio and other settings while I disconnected the battery. After removing the battery, I was amazed the trunk light stayed on, so just for grins I pulled the lever for the rear deck lid, and was amazed it actually popped open - without a battery. Then I pulled the lever for the front trunk and heard the click noise, even though the trunk was open. The bottom line is you can open the front trunk with a dead battery using one of these chargers, which has a built-in supply mode!

The Optima 34R fits in the 997 just as easily as in my 986. It's easier to remove the left and right plastic covers as well, and these come off easier than on a 9x8. The trick I remembered was to take off the ground cable, install the battery, then reinstall the ground cable and orient it so it's long enough. I tied off the vent tube out of the way in case I ever put in a conventional flooded battery. Otherwise it's just like installing any other battery.

I've got some of the 3/8" HDPE sheet left over, so if any RennTech contributing members near me want one, let me know and a piece is yours for as long as I have any material left.

Here are the pictures of the completed install

post-84-099602100 1285004687_thumb.jpg post-84-082906200 1285004726_thumb.jpg

Link to comment
Share on other sites

The other weekend I finally got around to installing an Optima battery to replace the original 5 1/2 year old Porsche battery in our '05 997. I made a simple mounting base for the Optima 34R from 3/8" thick HDPE sheet. I plugged my CTEK 7000 battery maintainer in to the cigarette lighter socket hoping to maintain radio and other settings while I disconnected the battery. After removing the battery, I was amazed the trunk light stayed on, so just for grins I pulled the lever for the rear deck lid, and was amazed it actually popped open - without a battery. Then I pulled the lever for the front trunk and heard the click noise, even though the trunk was open. The bottom line is you can open the front trunk with a dead battery using one of these chargers, which has a built-in supply mode!

The Optima 34R fits in the 997 just as easily as in my 986. It's easier to remove the left and right plastic covers as well, and these come off easier than on a 9x8. The trick I remembered was to take off the ground cable, install the battery, then reinstall the ground cable and orient it so it's long enough. I tied off the vent tube out of the way in case I ever put in a conventional flooded battery. Otherwise it's just like installing any other battery.

I've got some of the 3/8" HDPE sheet left over, so if any RennTech contributing members near me want one, let me know and a piece is yours for as long as I have any material left.

Here are the pictures of the completed install

post-84-099602100 1285004687_thumb.jpg post-84-082906200 1285004726_thumb.jpg

Nice install and excellent tips!

How is the battery fastened to the HDPE plate?

Regards, Maurice.

Link to comment
Share on other sites

How is the battery fastened to the HDPE plate?

10-24 x 1 1/4" stainless steel flat head phillips head machine screws (quantity 4) from the bottom of the HDPE plate. The screws aligned with the holes on the Optima battery, then a washer and #10 stainless lock nut. I countersunk the screw holes so the heads were flush with the bottom of the plastic. Very simple, but easy to just unscrew the 4 screws in the future, replace the Optima with a new one, and then screw it back together. I made the mounting plate the same size as the old battery so I could just use the existing Porsche mounting clamp. It was about 12 1/4" x 6 7/8", same as I did for my 986 in this topic

I'm out of town all this week, but can post pictures when I get back of the mounting plate I made if anyone is interested

Link to comment
Share on other sites

How is the battery fastened to the HDPE plate?

10-24 x 1 1/4" stainless steel flat head phillips head machine screws (quantity 4) from the bottom of the HDPE plate. The screws aligned with the holes on the Optima battery, then a washer and #10 stainless lock nut. I countersunk the screw holes so the heads were flush with the bottom of the plastic. Very simple, but easy to just unscrew the 4 screws in the future, replace the Optima with a new one, and then screw it back together. I made the mounting plate the same size as the old battery so I could just use the existing Porsche mounting clamp. It was about 12 1/4" x 6 7/8", same as I did for my 986 in this topic

I'm out of town all this week, but can post pictures when I get back of the mounting plate I made if anyone is interested

Geoff:

Thanks for the detailed explanation. I didn't know the Optima had ears that you could screw into.

The more pics the better around here! biggrin.gif

Regards, Maurice.

Link to comment
Share on other sites

It's not a good idea to be using a battery charger on a vehicle without a battery installed as the charger can spike in voltage and damage components.

I've got the CTEK 7000, but there's a slight update called the 7002. On CTEK's web site at http://www.ctek.com/EN-US/consumer/mus-7002.aspx they say "Thanks to its SUPPLY mode the battery charger provides power even without a battery. The SUPPLY mode is indispensable when changing the battery as you avoid losing complicated program settings." Based on their design with this functionality, I used it to keep from losing settings. The 7000 is a higher end version of their 3300 model, which is what Porsche rebrands and sells.

Link to comment
Share on other sites

Well I learn something new everyday. I know that battery chargers can cause problems but I still wouldn't use a maintainer and start operating locks/power windows and such just incase. I've never tested the output of these CTEK units so maybe they can be stable enough without problems.

Link to comment
Share on other sites

Something I forgot to include in my original post: The original Porsche Moll battery weight 47.2 lbs when I measured it (not sure how much water evaporated from the cells), and the new Optima weighed 40.6 lbs. The mounting plate I made and fasteners weighed much less than a pound

Link to comment
Share on other sites

  • 5 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.