4-34. ADJUST BRAKES (CONT).
Measure distance between center of
large clevis pin (7) and bottom of brake
chamber (1), (measurement A) with brake in
released position. Record measurement.
The free stroke sets the
clearance between the linings
and brake drum.
If when checking free stroke
as part of Preventive
Maintenance, the free stroke is
not within specifications, refer
to troubleshooting (Para 4-16)
to correct the problem prior to
The difference between
measurement B and
measurement A is the free
stroke. Free stroke must be
between 5/8 to 3/4 in.
Using a pry bar, move slack adjuster (3) so
that linings (5) are against drum (6).
Measure the distance from center of large
clevis (7) to bottom of brake chamber (1)
again, (measurement B).