Skylark V6-181 3.0L (1986)
During normal braking operation, the proportioner valve is not functional. Brake fluid flows into the proportioner valve between the piston center
hole and the valve stem, through the stop plate and to the rear brakes. Spring pressure loads the piston during normal braking, causing it to rest
against the stop plate.
On diagonally split brake systems, two proportioners are used. One controls the left rear brake, the other the right rear brake. The proportioner
valves are installed in the master cylinder rear brake outlet ports.
