NOTE:
The close fitting piston backup ring (6) may
be depressed slightly to one side to lodge it in the
brake cylinder bore and temporarily hold the pres-
sure plate and springs in place while the brake cylin-
der is inverted and lowered over the motor adapter.
As an alternate, the motor adapter and brake plates
can be turned over and installed into the brake cylin-
der, holding the brake plates and spacer in place
through the center opening. Be careful to not pinch
your fingers between the spacer plate and the pres-
sure plate.
7. Apply petroleum jelly or an oil soluble grease to the
sealing surface of the brake cylinder and the piston
seal. Turn the brake cylinder over and lower it onto
the motor adapter, being careful not to damage the
piston seal or O-Ring on the adapter. Be careful the
O-Ring (13) does not fall out of place, and the oil
passages are aligned. The alternate assembly
method above could also be used.
8. Turn the entire assembly over and install the four
capscrews and lockwashers. After the capscrews
make contact with the motor adapter, evenly tighten
them one turn at a time until the motor adapter is
drawn tight against the brake cylinder, then torque to
the recommended value.
BRAKE CYLINDER PRESSURE TEST
1. Install a -6 ORB fitting into the brake release port on
the motor adapter. Connect a hand pump with an
accurate 0-2,000 psi (0-13,800 kPa) gauge and
shut-off valve to this fitting. Apply 1,000 psi (6,900
kPa) to the brake and close the shut-off valve. Let
the unit stand for five minutes. If there is any loss of
pressure, the brake cylinder should be disassem-
bled for inspection of the sealing surfaces, seal and
O-Ring. When the source of the pressure leak has
been determined and corrected, re-assemble the
brake cylinder and repeat the test.
2. WHILE PRESSURE IS APPLIED AND THE BRAKE
IS RELEASED, install the over-running clutch
assembly into the brake pack. Turn the clutch back
and forth to align the splines on all the friction discs.
Release the pressure on the brake cylinder and
remove the clutch assembly. The brake cylinder is
now complete and ready to be installed in the hoist.
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