All,

I have replaced my 964 Master Cylinder and booster with the 993 version and finally gotten rid of all the air in the lines and have a nice and firm brake pedal. The brake application point is lower than it used to be which in itself doesn't bother me because it lines up with the accelerator for easy heel and toe, but has a side effect of the brake pedal not reaching the microswitch that operates the brake lights.

Based on a comment found in an old Rennlist Thread "The 993 vacuum cannister rod is about an inch shorter than the 964, so you have to adjust the rod at the brake pedal to make up for this. Has your friend done that?" I pulled the floor board to access the pedal cluster. As you can see from the picture, it seem pretty straight forward to make the adjustment by adjusting the nut in the yellow oval(for informational purposes, the microswitch is in the green oval). What seems to be an easy job is not so easy I assume because of the brake pedal return pressure.

So, how do I reduce the brake pressure enough so I can turn the nut? I tried to open a caliper with 0 pressure in the system and that didn't help enough. So, what is the catch?



Thanks!

-Skip