Inspection. - TM-10-3930-622-140093

d. Inspection.

(1) Remove ball stud used on the control valve end of

the cylinder by removing the dust cover, and split collar

(1) Discard all sealing elements and scrapers and

clamping bolt on the ball stud housing, and unscrewing

replace with new, upon reassembly. Wash all parts in a

the ball stud from the housing.

good grade of mineral spirits.

(2) Loosen and remove the four capscrews that secure

(2) Inspect all fluid passages in valve body and

the control ball stud housing and valve assembly to the

cylinder to be certain they are clean and free from

cylinder. Remove the control ball stud housing and valve

obstructions.

assembly from the cylinder. Remove three packings

from recesses in the body.

(3) Check each disassembled part for excessive

wear, cracks, or pitting that would render them unfit for

CAUTION

continued use. Replace all defective parts.

Care must be taken not to score or

(4) Inspect valve spool for. deep scoring and

otherwise damage the cylinder or valve

excessive wear. Check valve spool bore for similar

mating surfaces.

scoring or pitting. Replace these parts if badly damaged

or worn. Do not rework or attempt to "touch-up" the

(3) Hold control ball stud housing and valve assembly in

valve spool. This practice will only result in improper

a vise, by lightly clamping valve body. Use care not to

steering unit operation and performance.

distort spool bore in valve body. Remove the wire ring

which locks the control ball stud sleeve plug and remove

(5) Inspect cylinder shaft for

damage

and

plug. Remove control ball stud, two ball stud seats,

straightness to insure proper sealing.

spring washer and spacer.

e. Control valve assembly.

(4) Remove self-locking nut from capscrew. Remove

capscrew, washer and control ball stud sleeve. Then lift

NOTE

the two centering spring retaining washers, centering

Immerse all parts in clean hydraulic fluid to

spring and spacer from the valve body. Remove control

facilitate reassembly. Refer to Figure 6-13

spool from the control ball stud end of body. Remove

and proceed with reassembly. Be sure that

packing from valve body and from spool to complete

all oil seals, wipers, and packing are

disassembly.

discarded and replaced with new parts for

reassembly. Remember that a seal can only

NOTE

do its job when properly seated to prevent

fluid leakage and entrance of air into the

The check valve retaining plug with integral

system. Coat all seals with liberal amounts

valve body-cylinder locating pin should be

of GAA or petroleum jelly prior to assembly.

removed for inspection.

(1) Install new packing (coated with grease or

c. Cylinder disassembly. The cylinder assembly is a

petroleum jelly) in cylinder end of valve body and on

sealed unit. Overhaul procedures are restricted to

control ball stud end of valve spool. Install spool in bore

replacing the sealing parts on the rod end.

from the control ball stud end to avoid packing

interference during assembly.

(1) Remove anchor ball stud by removing nut, bolt,

and lockwasher from the ball stud housing and

(2) Install washer, spacer, centering spring, washer,

unscrewing the ball stud.

control ball stud sleeve, capscrew washer and capscrew.

Install self-locking nut and tighten until play between

(2) Remove retainer snap ring with snap ring pliers.

parts is removed. Be sure that nut is in good condition

Rotate the rod and withdraw it far enough from the

and that the centering spring remains aligned between

cylinder to expose scraper, wiper ring, retainer and

the two remaining washers. Back nut off one flat (1/6

washer. The shaft seal assembly may be removed with

turn or 60 degrees).

a hooked scriber.

(3) Start control ball stud sleeve plug in control ball

(3) Steel seat ball stud assemblies used can be

stud sleeve.

disassembled for inspection. First remove the cotter

pin,, plug, spring and outside seat. Then remove the ball

(4) Slide the control ball stud housing over the ball

stud nut, spring, shield and dust cover. Remove the ball

stud sleeve.

stud, the other seat and the grease fitting.

(5) Install the studs which attach the valve to the

cylinder, if they were removed.