Section IV. GENERAL HYDRAULIC SYSTEM REPAIR METHODS

TM 5-2420-224-34

GENERAL LUBRICATION INSTRUCTIONS

Keep a light coat of lubricating oil on parts during repair procedures to prevent rusting.

Lubricate parts during repair and assembly as required by LO 5-2420-224-12.

GENERAL TORQUE VALUE INSTRUCTIONS

Use the torque values listed in the maintenance Procedures, if they are given. When no torque

values are given in the maintenance procedures, refer to the torque value guide in Appendix D.

Section IV. GENERAL HYDRAULIC SYSTEM REPAIR METHODS

OVERVIEW

This section contains repair methods for the hydraulic system. If special repair methods or

procedures are required for the hydraulic system or related parts, these methods or procedures are

included in the individual maintenance procedures in Chapters 3 thru 21.

GENERAL REPAIR METHODS

WARNING

High pressure hydraulics [oil under 2450 psi (16,893 kPa)] operate this

e q u i p m e n t . Never disconnect any hydraulic line or fitting without first dropping

pressure to zero. A high pressure oil stream can pierce body and cause

s e v e r e injury to personnel.

CAUTION

Always clean around fittings before disconnecting or connecting hose of

fittings. Make sure area is clean before installing hydraulic components.

F a i l u r e to do so could result in damage to equipment.

Cover, cap, or plug all openings, ports, and tube or hose ends when

d i s c o n n e c t e d . Failure to do so could result in damage to equipment.

M a t e a fitting only with a fitting designed to mate. Because two fittings will

screw together is no guarantee they will not leak. Never depend on trial

a n d error. To do so could result in damage to equipment.

F i t t i n g s must be installed and hand-tightened. If a fitting cannot be hand-

t i g h t e n e d , it may be cross-threaded or have damaged threads. Use wrench

only for final tightening. Failure to do so could result in damage to equipment.

Do not use pipe dope as sealer on any fitting. Pipe dope can separate from

fittings causing control valves and relief valves to become contaminated and fail.

I t is possible to screw a male NPT into a female straiqht thread, but fitting

w i l l leak. NPT has a slight taper.