3-7. Boom Cylinder Assembly. - Continued
b. Repair. (figure 3-1)
There are two cylinder assemblies, disassembly of each one is the same.
Discard all preformed packings, back-up washers, seals, sealing ring, retainer and rod
Remove retaining ring (1) from gland (2).
Remove three piece retainer (3) and gland (2) from piston rod (4).
(3) Remove rod scraper (5), cup (6), back-up washer (7) and packing (8) from gland (2).
(4) Remove piston rod (4) from tube (9) and remove spacer.
(5) Remove locknut (n), bearing ring (12), two back-up rings (13), crown seal (14), hydraulic piston
(1 5), and packing (16).
Dry cleaning solvent, PD-680, used to dean parts is potentially dangerous to personnel and
property. Avoid repeated and prolonged skin contact. Do not use near open flame or exces-
sive heat. Flash point of solvent is 100ºF-138°F (38°C-60°C).
(6) Clean external parts of cylinder assembly using dry cleaning solvent and dry thoroughly.
(7) Clean internal parts using lubricating oil.
(8) Inspect cylinder assembly components for nicks, scratches, cracks or thread damage and re-
place any damaged parts.
(9) Install packing (16), crown seal (14), two back-up rings (13), and bearing ring (12), on hydraulic
(10) Install rod scraper (5) and cup (6) into bore of gland (2).
(11) Install back-up washer (7) and packing (8) on gland (2).
The gland must be seated squarely inside piston bore and on piston rod. Cocking, however
slight, may damage seals and result in failure of the boom cylinder assembly.
(12) Apply lubricating oil to piston rod, and install gland (2) onto the piston rod (4).