TM
5-4310-275-14
WARNING
and tighten with a torque of 25 pound-inches
Dry cleaning solvent, Fed. Spec. P-D-680
(.2904 kgm).
or P-S-661, used to clean parts is
(7) Install air intake filter (5), cover (3), and
potentially dangerous to personnel and
two gaskets (4) with screws (1) and lockwashers
property. Avoid repeated and prolonged
(2).
skin contact. Do not use near open flame
(8) Connect the intercooler assembly (fig. 7-
or excessive heat. Flash point of solvent
1).
is 100 F. (38 C.) -- 138 F. (59 C.).
7-7. Second Stage Cylinder, Piston and Valve,
b. Cleaning and Inspection.
Removal and Installation
(1) Clean all parts with dry cleaning solvent,
a. Removal.
Fed. Spec. P-D-680.
(1) Disconnect the intercooler assemblies at
(2) Inspect all parts for obvious indications
the second stage inlet and outlet ports (fig. 7-1).
of damage, such as damaged screw threads,
scratched, pitted, or worn finished surfaces, and
relief valve assembly (29),
broken cooling fins.
(3) Unscrew cylinder cap (42) and remove
(3) Inspect the cylinder bore, piston, piston
exhaust valve (35), valve spring (36), valve spring
pin, master rod, and bearings for excessive wear,
washer (37), and preformed packing (38).
scoring, and. other damage.
(4) If the rupture disc (41) is defective,
(4) Refer to Table 5-2 for wear tolerances.
unscrew disc holdown screw (39) and remove disc
c. Reassembly.
retainer ring (40) and rupture disc (41) from the
(1) Attach first stage piston (23, fig. 7-2) to
cylinder cap (42).
master rod and needle bearings with piston pin
(5) Remove nuts (33) and carefully slide
(22, fig. 7-2) and retaining rings (21).
cylinder (34) over the piston assembly (28).
(2) Install shim (25) between two paper
(6) Remove and discard gaskets (22 and
gaskets (24), against mounting flange of first
shim (23) .
stage cylinder (19).
(7) Remove cotter pin (26) and carefully
(3) Slip first stage cylinder (19) over in-
push piston pin (27) out of the piston assembly
stalled piston and press into crankcase mounting
(28). Use care to prevent loss of the twenty-five
hole, Cylinder must be installed with leading edge
needle bearings (24) and two washers (25) which
of cooling fins slanted toward fan end of com-
will drop out of the piston assembly when the
pressor. Secure cylinder to crankcase with nuts
piston pin is removed. Scribe a small mark on the
(20), being sure to tighten with an equal torque.
inside of the piston skirt toward the fan end of the
(4) Use a depth micrometer or dial indicator
crankcase for correct reassembly.
to measure piston-head-to-valve-plate clearance.
(8) Do not disassemble the piston assembly.
Required clearance is 0.021 to 0.026 inch (.0533 to
.0660 cm). If necessary, remove cylinder and add
KEY to Figure 7-3.
1. Third stage disc retaining
22.
Gasket
or remove cylinder-to-crankcase gaskets to obtain
ring
Shim
23.
required clearance.
Bearing
2. Disc retainer
24.
NOTE
Washer
3. Rupture disc
25.
Overall thickness of steel gaskets can be reduced
Cotter pin
4. Third stage cylinder cap
26.
in increments of 0.002 inch (.0050 cm) by peeling
Piston pin
5. Exhaust valve spring
27.
off laminations. At least one paper gasket must
Piston assembly
6. Exhaust valve
28.
remain on each side of steel gasket in final
Relief valve assembly
7. Elbow
29.
installation.
Nut
8. Nut
30.
(5) Install packing (10) in groove in first
Preformed packing
9. Preformed packing
31.
Seal
10. Gasket
stage cylinder head (9). Assemble valve stop (11),
32.
Nut
11. Third stage cylinder and
33.
exhaust spring (12 ), exhaust valve (13), valve
sleeve
Second stage cylinder
34.
plate (14), intake valve (15), and intake valve
12. Nut
Second stage exhaust valve
35.
13. Seal
spring (16), Attach assembled parts to cylinder
Valve spring
36.
14. Reducer bushing
head with screw (18), flatwasher (17), and screw
Valve spring washer
37.
15. Bearing
Preformed packing
38.
(8) .
16. Washer
Disc holddown screw
39.
(6) Position first stage cylinder head and
17. Cotter pin
Disc retainer ring
40.
18. Piston pin
valve assembly and gasket (17) on first stage
Rupture disc
41.
19. Piston assembly
cylinder so that cooling fins all slant in same
Cylinder cap
42.
20. Gasket
21. Gasket
