Have replaced the brake lines, master cylinder and booster on my 69 Z28. Bled the brakes and noticed a minor fluid leak from the rear of the round metering valve. Ordered a rebuild kit from HBC which consisted of three parts: the external rear button boot, the front o-ring and the rear cup rubber seal (which mine did not have in it when I disassembled it). Too bad the rebuild kit does not include the internal flat washer!
Before I disassembled and now upon reassembly I noticed the bypass button on the rear of the metering valve cannot be pushed in, even when placed in the vice.
I measured the length of the parts and then the length of the internal cavity in which they go when assembled and the distances are the same. What gives? No way for the rear button to push in! I have searched the several threads on this site and over at Team Camaro. No one seems to have run across this.
I think there are a couple different designs of this metering valve but mine is like some others whose internals are shown on the various threads. How mine did not leak with out the rear cup seal before I replaced the other components of the system I do not know. Any thoughts from any one?