A relative of mine several months ago installed a new brake master
cylinder in his  Vanagon. It was a Bietrix brand, whatever that is.
Since then he has complained about the brakes not always working well
and recently stopped driving it because it did not feel safe to him.
Today I visited him and we looked at his problem. Every push on the
brake pedal made a strange noise that sounded like air rushing. The
pedal went most of the way to the floor. Holding it down while starting
the engine had no affect.

I brought along a used pedal cluster with booster and he installed the
used master cylinder from that assembly. The noise stopped and the pedal
was much higher with a firmer feel. Holding the pedal down while
starting the engine resulted in the pedal moving farther as brake system
vacuum built up. All was good, test drove fine.

Has anyone here used that brand of master cylinder? How did it work out?

thanks,
Mark