18-12. BOOM CYLINDER FLOW CONTROL VALVE REPLACEMENT
This Task Covers:
Tools and Special Tools
Tags (Item 39, Appendix C)
Tool Kit, General Mechanic's: Automotive
Container, 1 gal (3.79 l) capacity
(Item 18, Appendix F)
Cap and Plug Set (Item 3, Appendix F)
Jackstands (Item 7, Appendix F)
Boom fully lowered and attachment resting on ground
Transmission cover removed (Para 16-5)
· Hydraulic oil in system can be under pressures over 3000 psi (20685 kPa) with engine OFF.
ALWAYS relieve pressure in hydraulic lines before attempting to remove any component in
hydraulic system. With engine OFF, starter switch in RUN position, and attachment on ground,
move control levers through all operating positions several times to relieve line pressure. Relieve
pressure in hydraulic oil tank by loosening filler cap very slowly. Failure to follow these
precautions could result in serious injury to personnel.
· At operating temperatures, hydraulic oil is hot and under pressure. Hot oil can cause injuries to
personnel. Allow hydraulic oil to cool before disconnecting any hydraulic lines.
· When working underneath boom, always support boom using blocks, jackstands, or other rigid and
stable supports. Combined weight of boom and attachment is approximately 6300 lb (2857.63 kg).
Failure to adequately support boom could result in severe injury or death to personnel.
Wipe area clean around all hydraulic connections to be opened during removal and disassembly. Cap
oil hoses and plug holes. Contamination of hydraulic system could result in equipment failure.
Use suitable container to catch any hydraulic oil that may drain from system.