expansion tank cap

[devans]

Wonder if anyone can tell me whether the spring in the cap of the expansion tank should be quite hard to press by hand. All other cars that i have had have had extremely stiff springs.
The reason i ask is that from time to time i seem to lose water from the expansion tank. It can go weeks being ok, but then all of a sudden the red warning light flashes slowly. This is due to the expansion tanks loss of water as it goes well below the minimum line.
I know the cars expansion tanks are prone to hair line cracks as i have seen much debate on the forum, however, i would prefer to try a replacement cap first if you all agree that the spring should be fairly stiff.
Any thoughts!!!!

David

 

[Bull996]

Check the number on the cap. If it ends in 01 then its OK-the earlier ones are prone to failure. Other than that, the tanks themselves are known to crack, usually on the underside and only leak when very hot and high pressure.

 

[devans]

Just checked the part number...996.106.447.00. Its on my 1998 C2.
It doesn't take much force to push the spring in and it definately does not finish with an 01.
If the earlier ones are prone to failure, then maybe a new cover is due.
Many thanks for your comments. Hopefully more replies may well confirm this!!!!
David

 

[Richard_Hamilton]

Philip's right. Check the number on the cap. If it ends in 00 ditch it and get a new one - it was a common problem for them to leak. If the cap leaks the water goes into the catch tray around the top of the tank, and down a tube onto the floor. Check for staining or damp patches on the panels under the coolant tank after a good run. If there are signs then it's the coolant tank.

 

[Guest]

I have exactly the same problem on my MY98 996.Every couple of weeks the red light on my temp gauge flashs(although temp stays constant).I checked my cap today and it ends in 00.The spring is easily compressed.Where do I get a new '01' cap-must I go thru OPC or is there someone online who I can order it through?
Paul.

 

[Richard_Hamilton]

You can get them from www.eurocarparts.com. £8.67 + VAT & carriage. Once you have selected your vehicle, go to Cooling>Expansion Tank.

Edit: Porsche part number for the cap is 996.106.447.01

 

[Guest]

Thank you Richard.

 

[devans]

Just replaced mine today.
Got it from euro car parts...off the shelf.
Thanks for all the help.
David[]