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2.4 — Service Procedures
The service section covers replacement of valve plates and
gaskets, service to the bearing head assembly containing the
oil pump, and a clean-up procedure to follow in case of
motor burn out. Most other internal service requires replace-
ment of the compressor.
REMOVE, INSPECT AND REPLACE CYLINDER HEAD
AND VALVE PLATE ASSEMBLY
To test for leaking discharge valves or blown cylinder head
or valve plate gaskets:
1. Pump compressor down.
2. Observe suction and discharge pressure equalization. If
valves are leaking or a gasket is blown, the pressure will
equalize rapidly.
Maximum allowable discharge pressure drop is 3 psi per
minute after initial drop of 10 to 15 psi in first half
minute.
New reed valves may require 24 to 48 hour run-in time
to seat completely.
A compressor bank (head) with a blown gasket can also
usually be detected by touch since the head temperature
will normally be much hotter than a bank with good
gaskets.
3. If there is an indication of loss of capacity and discharge
valves are functioning properly, remove valve plate
assembly and inspect suction valves.
NOTE: This test procedure is not applicable to compres-
sors equipped with pressure actuated unloader valves
due to rapid pressure equalization rate. Inspect suction
and discharge valves by disassembling valve plate.