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5. To check brake stack height, place pressure plate on top
of brake spacer. Hold pressure plate down firmly by hand
and measure clearance in three places between motor
support and pressure plate. Average gap must measure
between .153 inch (4 mm) maximum and .080 inch (2
mm) minimum. If the gap exceeds the maximum limit,
there are too many brake discs in stack-up or the discs
are distorted. If the gap is less than the minimum, there
are too few discs in stack-up or the discs are worn out.
When stack height is correct, remove pressure plate and
continue assembly.
6. Lubricate the brake piston seal and motor support sealing
surface with petroleum jelly or hydraulic oil. Install new
piston seal to motor support, seal lip down.
7. Install the spring spacer, then the brake springs.
8. Install pressure plate into brake cylinder followed by the
piston backup ring.
9. Install the small brake-release O-ring into the groove us-
ing petroleum jelly.
10. Apply petroleum jelly to the entire sealing surface of the
brake cylinder and to the piston seal. Align the brake-re-
lease port of the motor support to that of the brake cylin-
der. Lower the motor support into the brake cylinder; be
careful to avoid damaging the piston seal or motor sup-
port O-ring. (A press may be necessary to avoid cocking
the brake cylinder during installation.)
11. Confirm that the brake-release ports are aligned with the
small O-ring in place.
12. Install motor support capscrews and tighten evenly to
recommended torque.
Always use the molded spring spacer with the new brake
cylinder. The brake springs must be properly positioned
by the spring spacer. Failure to install the spring spacer
may allow the springs to contact each other and become
damaged. This could result in loss of load control, prop-
erty damage, injury, or death.
