b. Disassembly (fig. 27).
(1) Remove the two flathead screws (36) and disassemble the air cylinder from the mounting bracket (37).
(2) Remove the drilled bearing pin (14) and bearing block (16) from the bell-cranks (15 and 17). Remove the
special cotter pin (18), drive out the bearing pins (11 and 13) and remove the bell-cranks (15 and 17) from
the cylinder head arm and the rod connecting block (19).
(3) Remove the connecting block (19) and hex jam nut (2) from the end of the piston rod (10).
(4) Take out the two roundhead screws (21) and lockwashers (22) and disassemble the shutter lock (20), lock
clips (23 and 24), dust cap retainer (25), dust cap (26), felt (27) and washer (28) from the cylinder head (32).
(5) Remove the four roundhead screws (30) and lockwashers (31) and carefully remove the cylinder head (32)
and its gasket (33) from the cylinder body. Slide the retainer ring (35) and lubricator felt (34) from the
bearing boss on the inside of the cylinder head.
(6) Pull the piston rod (10) from the cylinder body (1) and slide the spring (9), large piston head (7), piston cup
(6), washer (5), piston cup expander (4) and small piston head (3) from the rod.
c. Cleaning and Inspection.
(1) Clean all parts thoroughly with cleaning solvent and blow dry with compressed air.
(2) Examine the piston cup carefully for damage or excessive wear. At regular overhaul periods, it is advisable
to replace the piston cup and cup expander.
(3) Replace any broken parts with new ones.
d. Reassembly and Adjustment (fig. 27).
(1) Saturate the lubricating felts (8 and 34) with light machine oil during reassembly. Also, apply a film of light
machine oil to the inside surface of the cylinder body (1).
(2) Install the small piston head (3), piston cup expander (4), washer (5), piston cup (6), large piston head (7)
and spring (9) onto the piston rod (10). Assemble the lubricator felt (8) to the large piston head. Insert this
assembled group into the cylinder body, using a compression sleeve to avoid scuffing the edges of the
piston cup.
(3) Position the lubricator felt (34) and retainer ring (35) over the bearing boss on the inside of the cylinder head
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