Subaru Legacy 2002 Service Manual page 2173

Brake
5) Install seal to reservoir tank.
(1) Seal
6) Install pin with drift pins which secures reservoir
tank to master cylinder.
MASTER CYLINDER
E: INSPECTION
If any damage, deformation, wear, swelling, rust,
and other faults are found on the primary piston
assembly, secondary piston assembly, supply
valve stopper, or gasket, replace the faulty part.
CAUTION:
¼ The primary and secondary pistons must be
replaced as complete assemblies.
¼ The service limit of the clearance between
each piston and the master cylinder inner dia.
is 0.11 mm (0.0043 in).
B4M1450C
¼ When handling parts, be extremely careful
not to damage or scratch the parts, or let any
foreign matter get on them.
BR-34
S405168A10