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Old 03-08-2013, 12:06 PM
Dragan Dragan is offline
Officially Welcomed to the 'Fest
Location: Waterloo, Ontario
Join Date: Jan 2013
Posts: 194
Mein Auto: 2002 BMW 530i Sport 5 Spd
Originally Posted by bluebee View Post
Am I correct in assuming that, in normal operation, there is no venting going on, right?
Correct. The cap is simply a relief valve for safety purposes. I feel as if people are under the assumption that the cooling system operates at 2 bar. It's nominal operating pressure is likely much less. The system is always completely sealed unless it's exposed to atmospheric pressure either through the cap (which houses the relief valve) or through a leak somewhere in the system.

2002 530i Sport Package 5-speed
Style 42s for summer
Style 29s for winter
CDV delete
Skibag retrofit
G.A.S. DISA Valve Repair Kit
G.A.S. 1.2 Bar Expansion Tank Cap
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