TM 5-4310-375-14
4-19. Cylinder head, first and second stage valves. Maintenance of cylinder head, first and second stage valves at
organizational level is as follows:
a. Removal/Disassembly. Remove and disassemble in the following sequence.
WARNING
Drain air system before performing any maintenance. Open air receiver
drain cock.
(1) Unscrew and remove the six cylinder head bolts (1, fig 4-6). Tap the cylinder head lightly with a plastic
head hammer, or equivalent, to break the seal of cylinder head and valve plates to compressor cylinder.
(2) Separate cylinder head (2) and cylinder head gasket (3) from upper valve plate (4).
CAUTION
As an aid at assembly, mark the upper valve plate (4) and lower valve plate
(8) in a suitable manner on the edge of each so they are assembled in the
same sequence as removed.
(3) Separate the upper valve plate (4) from lower valve plate (8). Remove the two second stage valves (5),
two first stage valves (6), valve plate gasket (7), and cylinder gasket (9).
WARNING
Dry cleaning solvent, Federal Specification P-D-680, used to clean parts is
potentially dangerous to personnel and property. Avoid repeated and pro-
longed skin contact. Do not use near open flame or excessive heat. Flash
point of solvent is 100F - 138F (38C - 59C).
b. Cleaning. If gasket material has stuck to cylinder head (2, fig 4-6) or valve plates (4, 8), carefully scrape off
material. Clean all parts, except gaskets (3, 7, 9) with solvent, P-D-680, or equivalent, and dry thoroughly. Make
certain air passage holes in valve plates (4, 8) are free of any foreign matter.
c. Inspection. Visually inspect all parts for cracks, breaks, chipping, distortion, and evidence of wear. Any part
suspected of defect from this inspection shall be replaced.
d. Repair or replacement. No repair of these parts is authorized, Replace gaskets (3, 7, 9, fig 4-6) each time cylinder
head (2) is removed to ensure proper sealing at assembly. If second stage valves (5) or first stage valves (6) are worn or
damaged, replace all of the valves.
e. Reassembly/Installation. Reassemble/install in the following sequence.
(1) Place a new cylinder gasket (9, fig 4-6) in position on compressor cylinder. Position lower valve plate (8)
on gasket (9) with valve recesses facing up.
(2) Position valve plate gasket (7) on lower valve plate (8). Apply just enough grease (MIL-G-10924) or
petroleum jelly on ends of first stage and second stage valves (6, 5) to hold them in place. Assemble the
two first stage valves (6) and two second stage valves (5) in position on valve plates.
4-18
