Tim Cole wrote:
Dear 55:

The pedal going to the floor concurrent with brake fluid being sucked into the motor is a leaking power piston seal.

Pedal going to the floor without any other symptoms is the compensator valve.

Attached is a picture of an original compensator. The new kits are supposed to be good, but if you buy parts they should match the picture.

I used to buy exchange units from Max Merritt because they were good and because if the unit failed and killed someone I wouldn't be liable for a civil action. In the old days we used to do them ourselves, but we also had NOS parts and so no problems.

Those units used to be very reliable using NOS parts and the old type brake fluid which is not the same as the modern stuff.

The two features I really don't think highly of is the lack of a vent between the power piston seal and the vacuum chamber and the compensator valve which is just plain cheap.