There are a lot of questions that need to be asked to better define specific answers.
However, note the following general comments:
a) Please clarify comments on Hyd-Fluid
Level Level can be from leak or loss of Nitrogen pre-charge gas in accumulators.
High & Low Fluid Temp ???
Fluid Type – Specify Mfg and fluid designation
b) Filter problems ? Have you done fluid analysis to determine cleanliness? I can send you Fluid Filtration Handbook.
c) Deviation alarm – How have you determined sticking was from slide valve and not lack of actuator thrust?
d) Note that excess purging can cause excess internal erosion and valve damage. Do you have maintenance record from last overhaul that would show clearances set for valve internals?
e) Were pump problems from worn pump or was problem loss of pressure caused by PSV?
Are these problems resolved? Do you know valve design type?
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