pressure switch icks

[dan lephart]

Got a reman power master installation almost completed when we found fluid squirting from the area where the "new" pressure switch base touches the master cylinder at the 1:00 position. The old pressure switch from the unit that was replaced was installed and it did not leak (old pressure switch causes the unit to chatter...). The old O ring did not stop the new switch from leaking. I used an oversized O ring and the "new" pressure switch stopped leaking. Got a "new"
replacement pressure switch today, same deal. It leaked at the 3:00 position and an oversized O ring stopped the leak. I am concerned that the oversized O ring is a temporary fix... You can see the oversized O ring squeezing through the outside of the master cylinder and the switch base. Any one?