Replacement of Filter Assembly

(2) Apply sealing compound, MIL-S-11031,

(1) Inspect hardware, check for broken or

to the threads of screw (6) anti install. Tighten screw

worn threads, rust or corrosion.

until the plunger bearing seats into the groove on side of

(2) Inspect gear, check for cracked, chipped

filter assembly (10) housing. Use the lever to rotate the

or broken teeth, rust or corrosion.

filter assembly. The plunger should permit rotation but

c. Repair Repair is limited to replacement of worn

hold the filter assembly in each position. Tighten or

loosen screw as required.

or damaged parts.

(3) Install setscrew (5) and apply sealing

compound, MIL-S-11031. over head of the setscrew.

d. Assembly.

(1) Apply a thin film of grease, MIL-G-23827,

to the teeth of gear (12, fig. 3-12) and to the segment

3-17.

Replacement of Filter Assembly (Fig. 3-12).

gear installed in housing.

(2) Apply sealing compound, MIL-S-11031, to

a. Removal.

threads of stud (11, fig. 3-12).

(1) Refer to paragraph 3-15 for removal and

(3) Position gear to mesh properly with the

replacement of the objective tube assembly (4).

segment gear. Secure with the stud.

(2) Use adjustable spanner wrench to remove

(4) Install setscrew (2, fig. 3-13) until the tip

stud (9). Carefully pull filter assembly (10) from housing.

extends inside the housing. Setscrews act as stops to

the segment gear. Adjust setscrews to permit gear to

b. Inspection.

run to the outer limits of the segment while maintaining

(1) Inspect the filter assembly, check for

mesh with gear (12).

cracked or broken filters.

(5) Apply a thin coat of sealing compound,

(2) Inspect the stud, check for worn or broken

MIL-S-11031, over head of setscrew and install setscrew

threads, rust or corrosion.

(1, fig. 3-13) and again apply sealing compound, MIL-S-

(3) Inspect gear at rear of filter assembly

11031, over head of the setscrew.

housing, check for broken or chipped teeth, rust, or

corrosion.

3-19.

Repair of Parallax Adjustment Mechanism

(Fig. 3-13)

c. Cleaning.

(1) Clean metal surfaces with a cloth

a. Disassembly.

moistened with dry cleaning solvent.

(1) Unscrew item 3. Use adjustable spanner

(2) Clean each filter using lens tissue paper.

wrench to remove retainer (4).

d. Repair Repair is limited to replacement of the

(2) Remove screw (5) and peel packing (6)

from groove of the screw.

filter assembly and stud.

b. Inspection.

e. Installation.

(1) Inspect hardware and retainer, check for

(1) Apply grease, MIL-G-23827, to teeth of

worn or broken threads, rust or corrosion.

gear at rear of the filter assembly housing and to the

(2) Inspect packing, check for wear or

inside diameter of the mounting hole.

deterioration.

(2) Apply sealing compound, MIL-S-11031, to

the threads of stud (9). Position filter assembly (10),

c. Cleaning.

secure with the stud.

(1) Clean metal parts with a cloth moistened

with dry cleaning solvent.

3-18.

Repair of Filter Assembly

Operating

(2) Clean packing in warm water with a mild

Mechanism (Figs. 3-12 and 3-13)

soap. Dry thoroughly.

a. Disassembly.

d. Repair. Repair is limited-to replacement of worn

(1) Use adjustable spanner wrench

or damaged parts.

unscrew stud (11, fig. 3-12). Remove gear (12).

(2) Remove items 1 and 2, (fig. 3-13).

e. Assembly.

(1) Apply a thin film of grease, MIL-G-4343, to

b. Inspection.

packing (6)and install in groove of screw (5).

3-16