Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, ARE due Dec 6th, 2021. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

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)

Antifreeze Reservoir Tank Pressure Relief Valve


Recommended Posts

After a recent water pump replacement on my 1999 996, I filled the resovoir with 50/50 antifreeze as per instructions. The plastic high pressure releif valve keeps lifting indicating very high pressure in the tank. I believe that I may still have air in the system and that's why the valve extends upward after driving the car a few miles. This valve never lifted prior to the water pump R & R. Also, temperature at a red light creeps up to the middle of the zero at the "180" mark with A/C on. What is the normal operating temperature? Also, what is the correct procedure to purge the air out of the cooling system?

Thanks,

Harry

Link to comment
Share on other sites

As Loren said Filling with a vacuum filler is the correct way to fill.

If you have a lot of air you could damage the engine by driving, it can cause steam pockets/hot spots in the head.

That said sometimes you can purge the system by lifting the bail (snap it vertical) on the pressure relief valve when the car is cold and there is a vacuum in the system. This will often pull the AF out of the reservoir so you will need to refill it each time.

You will probably need to repeat this a couple of times to get most/all of the air out.

The needle creeping to the center of the "0" is not excessively hot., mine runs between the "8 & 0". On a hot day in stop and go traffic with the air on it will run on the "0"

The system is pressurized when hot, 1 bar-14.4 lbs, the valve lifting is normal operation.

Edited by fpb111
  • Upvote 1
Link to comment
Share on other sites

  • Moderators

The pressure relief valve act normal, when hot: valve on full lift, when cold: valve down. The valve will remain down (with hot engine) if the pressure cap is leaking or in case of a relatively large leak elsewhere.

Link to comment
Share on other sites

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.