[burgermeister]

I never did understand why on earth Porsche vented the brake reservoir to the atmosphere, when US manufacturers had been using the rubber bellows method since the 60's, and possibly earlier. Makes zero sense, except that Germans always know best, even when they don't.

Based on comments on the prior page - that drilling a hole in the top of the cap works - I'd think some small diameter copper tubing pushed through the plastic nipple so the vent point ends up in the center of the reservoir should work.

There is appropriately sized copper tubing available at FLAPS - the nipple on my reservoir broke off, and I used such tubing to splice it all together again. It was just a light press fit, holds pressure for power bleeder and otherwise works dandy. Even spills quarts of brake fluid when I forget to clamp the vent line.