Hi all, i thought I'd share a pic with you, this is the inside of my brake servo after a bit of rain stopped it from working, it must have been sucking the water up from the plenum for some time to get these tide marks

It's easy enough to split the servo and there was no damage to the diaphram, the air leak came from the build up around the sealing faces so I would have though you could clean this up and maybe use a bit of sealant instead of buying a new servo as i did

Remember to Check your plenum drain holes!!!