OP-755 Part 2 Pages 197-401 - Personal Page of GENE SLOVER

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After this period of operation examine the screens or filters
(if any) in the system and if any evidence of foreign matter
is found draw off all oil, clarify and refill.
Whenfilters remain clean, and only then, start moving the
controls, creeping very slowly and gradually building up speed
and power. During such operation watch for symptoms of valve
sticking, for evidence of binding of parts, and for leaks. At
the first sign of such condi tions stop operations, diagnose
the trouble and correct. Do not attempt to "work-out" stiffness)
lag) vibration) etc. Always stop the machine) locate
'and c o r r e c t the t r oub l e.
MAINTENANCE
11. After a hydraulic system has been thoroughly cleaned,
has passed a dynamic test, and is filled with clean hydraulic
oil of the proper specification it should perform sa t i sfactorily,
indefinitely and without serious trouble, provided:
that the simple instructions and precautions prescribed below
are observed.·· .
12. All hydraulic mechanisms should be exercised daily.
It is not necessary to train or elevate guns to their limits,
nor to put other gear to the limits of their cycles. It is
sufficient, if after oil has been raised to proper temperature
and response pressure throughout the system has been obtained,
to move parts rela ti ve to each other. This will prevent residue
from forming and galvanic action from starting with consequent
sticking of valves. Operate the machine with control at
slow and then at high speed: - if it has selecti ve control operate
it similarly in each. Such daily exercise not only benefits
the mechanism as indicated, but equally important, it
trains personnel to observe the quickness of response, the
general performance, and to loca te trouble. The value of daily
exercise cannot be overstressed.
13. The hydraulic oil must be kept clean, neutral and
free of residue. The oil of all hydraulic systems should be
checked at least twice morit.h Ly+ for evidence of acidi ty and
sludge formation. When drawing test samples at drain points
inspect for water or evidence of rust formation. Evidence of
acidi ty, sludge or rust necessi tates immediate draining of the
system, flushing with acid free cleaning fluid, and thorough
drying with compressed air. All oil added to the system must
be carefully strained or filtered, or both, and salvaged oil
must always be clarified. Filters in the system must be opened,
examined and cleaned at regular periods (not less than once
monthly). Foreign matter in filters shall always, jf possible,
be identified as to source, and the parts producing theparticles
shall be dismantled and corrected, - making replacement
* New installations daily.