TM 5-3810-294-34
a. Remove two screws (1) and lock washers (2)
compressed air. Scrape all remaining gasket material
and remove discharge fitting (3) and gasket (4) from
from machined surfaces. Do not damage surface while
compressor.
scraping.
b. Remove flange gasket (5) from the base of the
compressor.
12-25. Inspection and Repair
c. Mark the cylinder head (18) and cylinder block
a. Remove nicks and burrs from machined
(34) to assure correct reassembly. Remove two screws
surfaces Replace parts with damaged threads. Replace
(6) and loosen cylinder head by breaking the gasket joint.
body if cracked or damaged beyond repair.
Lift cylinder head a]way from cylinder block. Remove
b. Replace worn inlet and outlet valves and valve
gasket (7).
seats.
d. Remove inlet connector (items 8 through 12)
c. Remove score marks from bearing bores and
e. Remove two discharge valve seats (17 caps (13)
machined surfaces of compressor body with a fine file or
from cylinder head (18). Lift out spring (14) and valves
handstone. Replace body if cracked or damaged beyond
(15) Remove plug (16).
repair.
f. Remove six plugs (19) from cylinder block
d. Replace piston if cracked or worn in ring
g. Remove both inlet valve spring (20), valves (21)
grooves. Replace worn or damaged piston rings.
and valve guides (22) from cylinder block
e. Remove scratches and score marks from
h. Working through the bottom of the compressor
bearing surfaces of crankshaft with a fine file or
body (57) remove four screws (23) and lock washers
handstone. Replace crankshaft if worn.
(24) from the connecting rods. Tap connecting rod caps
f. Replace cracked or damaged compressor body
(25) with a brass hammer to loosen and remove caps
Replace body if bores are worn or out of round.
and inserts (26). Push the connecting rod and piston
g. Replace worn or damaged compressor pulley.
assemblies out through the top of the cylinder block (34).
h. Replace damaged tube assembly or mounting
i. Using a piston ring expander, remove com
bracket.
pression rings (27) and oil scrapers rings (28) from
i. Replace all gaskets and packings.
pistons. Remove lock wires (29), press piston pins (30)
from pistons, and separate connecting rods (31) from
12-26. Reassembly and Installation Refer to figure
pistons (32). Press out bushings ('33)
and reassemble the air compressor as follows:
j. Mark the cylinder block (34) and compressor
a. Using a suitable press, press bearings (601 on
body (61) to assure correct reassembly. Remove six
crankshaft (58).
screws (36) and lock washers (37). Tap cylinder block
b. Align crankshaft and compressor body (61)
with a brass hammer to break the gasket joint and
according to removal markings.
Carefully press
remove the cylinder block from the compressor body.
crankshaft and bearing assembly into compressor body
Remove gasket (35).
with a suitable arbor press.
k. Remove unloader cup stop (38), unloader cup
c. Install packing (56) in rear cover (50) and press
(39), packing (40), unloader piston (41), and inlet valve
seal (57) in front cover (53).
seat (42) from cylinder block.
d. Install rear cover gasket (54), with oil hole in
l. Remove unloader spring saddle (43), spring (44)
gasket aligned with oil hole in body. Install rear cover
and unloader spring seat (45) from cylinder block. Press
(50) on body according to removal marks and secure
sleeve bearing (46) from body.
cover with four screws (48) and lockwashers (49).
m. Mark the end covers (50 and 53) and
e. Install gasket (55) and front cover (53) on body
compressor body (61) to assure correct reassembly
according to removal markings and secure cover with
Remove nut (47), eight screws (48 and 51) and
four screws (51) and lockwashers (52).
lockwashers (49 and 52). Remove front and rear covers
f. Install key (59) in crankshaft keyway.
(50 and 53) and gaskets (54 and 55). Remove packing
g. Press two unloader sleeve bearings (46) into
(56) from rear cover and press seal (57) out of bore in
cylinder block (34). Install unloader spring seat (45),
front cover.
spring (44) and spring saddle (43) in cylinder block.
n. Mark the crankshaft (58) and compressor body
h. Install four packings (40) on two unloader cups
to assure correct reassembly. Press the crankshaft and
(39) and unloader cup stops (38).
bearing assembly out of the compressor body (61).
i. Install two unloader cup stops, unloader cups,
Remove key (59).
unloader pistons (41) and inlet valve seats (42) in
o. Use a suitable bearing pulley and pull out
cylinder block.
bearings (60) from crankshaft (58).
j. Install gasket (35) on compressor body (61).
12-24. Cleaning
k. Install cylinder block (34) on compressor
Clean all metal parts in dry cleaning solvent (Federal
Specification
P-S-661)
and
blow
dry
with
12-12
