Mazda 323 Workshop Manual Supplement page 200

C1UTCl-i CONTROL
H
CLUTCH MASTER CYLINDER
'CHECK VALVE
RHD
CHECK VALVE
93GOHX-708
A hydraulic clutch master cylinder with a built-in check valve is used on the BP DOHC Turbo model.
This is to provide smooth
engagement
of the clutch
disc
by controlling (by the check valve) the flow of fluid
from the clutch release cylinder back to the master cylinder when the clutch pedal is released, thus cushion-
ing the impact "shock".
l-l-7