Assembly - TM-10-3930-621-340172

TM 10-3930-621-34

(2) Install sleeve screw (34) into tilt plunger (10)

10-47. Assembly

until firmly seated.

a. Refer to figure 10-12 and assemble as follows:

(3) Slide lower spring seat (35), spring (36), and

b. Install check valve poppets (5), springs (4), new

upper spring seat (35) on plunger (10) making sure

packings (3), and plugs (2). Reaching through inlet and

spring is seated evenly on seal lips.

outlet ports, press on face of check valve poppet to

(4) Place sleeve screw end of plunger in plunger

insure poppet is not binding.

cap (33) and slide lower seal plate (11) on plunger cap,

c. Assemble relief valve as follows: (1) Secure

alining mounting holes.

valve housing in vise, taking care not to damage

(5) Install lower ring (8) and lower seal (9) in

machined surfaces.

bottom of housing and insert plunger assembly slowly

(2) Install new packing (25) on barrel end of

through ring, seal, and housing.

poppet (26).

(6) Aline mounting holes of housing (37), seal

(3) Install backup ring (24) and poppet, barrel

plate (11), and tilt plunger cap (33) and secure plunger

end first, into hole end of sleeve. Poppet barrel end

assembly to housing with two socket head screws (32).

must seat firmly into sleeve against backup ring. Barrel

(7) Install upper ring (8) and upper seal (9) on

must not block sleeve hole opening.

plunger (10) and seat firmly in housing.

(4)

Install assembled sleeve in bottom of

(8) Install upper seal plate (11) and secure with

housing, tapered end of poppet last, until sleeve opening

two screws (12).

can be seen through the inlet port.

e. Assemble lift plunger as follows:

Caution:

Although adjustment of the

(1) Place valve in vise in horizontal position,

sleeve will move the sleeve opening within the inlet

taking care not to damage housing.

passage, the opening at no time should be blocked

(2) Using lift plunger (38) and plunger cap (29),

completely by moving it out of the inlet passage; or

assemble lift spool parts as instructed in procedure d.

proper pressure relief will not be made, resulting in

(3) Install adjusting screw (31) and nut (30) in

damage to the entire hydraulic system.

plunger cap (29). Lock nut in place on adjusting screw

(5) Install new packing on plug (28) and firmly

as marked during disassembly.

seat spring (27) in plug.

f. Install end plugs (6) and new packings (7 and

(6) Carefully place plug assembly spring (27) up

22).

against tapered end of poppet (26) and partially tighten

10-48. Installation

plug (28) in housing. Note position of sleeve hole

a. Install valve assembly on truck and secure with

through inlet opening.

If hole moves above inlet

screws (1, fig. 10-13), flat washers (15), and nuts (16).

passage, loosen plug (28).

b. Install hydraulic line fittings and poppets on

(7) Install pilot spring (20) on guide (21) and

housing and', noting tags on lines, connect hydraulic

seat guide firmly in top end of sleeve.

lines.

(8) Install new packing (7) on pilot plug (19) and

c. Secure lever links (11 and 12, fig. 10-13) to

screw plug into housing.

respective plungers (10 and 38, fig 10-12) with pins (10,

(9) Screw adjusting plug (18) into pilot plug (19)

fig. 10-13), flat washers (14), and cotter pins (13).

until it seats lightly on sleeve (23). Completely tighten

d. Adjust relief valve (para 10-49).

bottom plug (28). Check sleeve opening from inlet port

e. Install right side cowl on truck (TM 10-3930621-

and adjust plug (18) to maintain opening in passage.

12).

(10) Install adjusting screw (17) in adjusting plug

10-49. Relief Valve Adjustment

(18) until it is snug against pilot poppet.

a. Description. Two relief valve adjustments are

Caution: Do not turn adjusting screw too

necessary to properly adjust the control valve. The

tight against poppet, as entire valve sleeve may turn

overpressure adjustment must be made prior to the final

when it becomes necessary to loosen screw.

adjustment.

The overpressure adjustment is at a

Note. Final adjustment of relief valve is made

reduced speed and partial load. It compresses the

after control valve is installed on truck. Refer to

poppet spring, requiring pressure above the normal

paragraph 10-49.

setting to open the poppet. The final adjustment is at

(11) Install two copper washers (14 and 16),

high speed and full load. It moves the sleeve and poppet

lock nut (15), and cap nut (13) on adjusting screw (17).

assembly

gradually

up,

relaxing

the

poppet

d. Assemble tilt plunger as follows: (1) Place valve

in vise in horizontal position, taking care not to damage

housing.

10-27