TM 5-4310-278-15
ROTARY COMPRESSOR REPAIR INSTRUCTIONS
sure correct positioning during reassembly.
6-1. General
Mark the drive gear (17) for identification
purposes.
unit which consists of two matched, three-lobed
(4) TO remove rotors (26 and 27) from
rotors that operate within a closely fitted hous-
drive end bearing (31) and housing (28),
ing. One of the rotors is driven by the engine.
screw four 1/4-20 x 4 inch long cap screws
Opposite the drive end of this rotor is mounted
through the gear end plate (21) and into the
a gear that engages the mating gear on the
housing (28) to provide support for the hous-
driven rotor and imparts rotation to the driven
ing. Using an arbor press, simultaneously
rotor so that both rotors rotate in synchro-
press both rotors out of drive end bearings
nism. As they rotate, air is trapped between the
and rotor housing. Separate drive end plate
rotor lobes and the housing and moves with
(35) and housing (28).
the rotors from the intake side of the com-
(5) To remove rotors (26 and 27) from
pressor to the discharge side of the compressor
gear end plate (21) and bearings (24), replace
rotors and gear end plate assembly on the rotor
pressor, the lobe of one rotor engages the open
housing. Screw the -20 x 4 inch cap screws
area between lobes of the other rotor and
into the opposite end of the rotor housing.
forces the air out of it so that the air must pass
Place unit in press and press drive rotor out
through the discharge port.
first; press out driven rotor.
b. The rotors ride in ball bearings mounted
b. Cleaning and Inspection.
in the side frames. Covers are provided to re-
(1) Discard and replace all seals and
slinger is provided on the drive end of the
gaskets.
drive rotor to provide oil splash for lubrication.
(2) Ball bearings are normally replaced
At the gear end, the lower gear rides in the
at overhaul. If it is necessary to reuse the bear-
oil and provides splashing to lubricate both
ings, place them in a wire basket and immerse
them in a container of fresh approved clean-
vent oil from seeping into the air compression
ing solvent. Agitate the basket in the solvent
area.
to thoroughly flush bearings. Dry with com-
pressed air, taking care not to spin the bear-
ings. Dip bearings in clean engine oil and wrap
in paper to prevent entry of dirt.
a. Removal and Disassembly.
(3) Clean all other metallic parts with an
approved cleaning solvent; dry thoroughly.
(4) Inspect rotors for cracks, distortions,
the rotary compressor. Observe the special pro-
burrs, damaged bearing seats, scoring or other
cedures described below.
damage. Remove burrs or light scoring with a
(3) Match mark the drive end plate (35)
fine stone or crocus cloth.
and cover (5), the rotor housing (28), and the
(5) Inspect the rotor housing for cracks,
gear end plate (21) and cover (12) to in-
distortion, burrs, scoring, and other damage.
