Form No. R92.00 Rev. 10/03
Part (Item No.)
Inspection Procedure
Corrective Action
Barrel
Visually inspect the bores’ internal condition for the following
(3)
A. Localized polishing at edge.
A. Re-use as is.
(Continued)
B. Minute, longitudinal nicks.
B. Re-use as is.
C. Localized longitudinal nicks.
C. Replace part.
Flush reservoir
and circuit.
D. Localized seizure, scoring, discoloration
D. Replace barrel and
all piston and
shoe assemblies (5).
Check for correct
hydraulic fluid type,
temperature rise,
excessive pressure.
Correct as needed.
Inspect for bore wear as follows. Wash the barrel bore. Insert a
If no resistance,
piston completely into a bore. Cover the kidney-shaped hole
replace the barrel
in the barrel, and the center hole on the shoe. Withdraw
and piston assemblies.
the piston.
If there is resistance
the bore is reusable.
Measure each bore in four places, including one place deep
Replace the barrel if the
within the bore, where the piston doesn’t run.
difference in
measurements
exceeds .0004 in.
or .010 mm.
Port Plate
Visually inspect the surface for uniform minute concentric
Repair by lapping
(4)
scratches, or deep scratches on the plate.
until scratch is
removed. Do not
remove more than
.006 in. or .152 mm.
Maintain flatness
of .0002 in. or .005 mm.
Visually inspect for heat discoloration
Use as is. Lap if
excessively discolored.
Do not remove more
than .006 in. or .152 mm
Inspect for cavitation erosion between ports
Repair by lapping
until erosion is
removed. Do not
remove more than
.006 in. or .152 mm.
Piston
Inspect for shoe end play by pushing and pulling the shoe while
Replace piston
Assembly
holding the piston. If the shoe clicks, or if movement can be
assemblies as a set.
(5)
seen, the piston assembly is excessively worn.
Check circuit suction
pressure. If less than
-5 in. Hg., raise fluid level
in reservoir, clean intake
strainer and/or correct
faulty circuit design.
Visually inspect shoe face for localized polishing, or random
Repair by lapping
radial marks.
assemblies as a set.
Shoes may be lapped
up to .004 in. or .102 mm.
Difference in shoe flange
thickness between the
thinnest and thickest of
nine shoes should not
exceed .0012 in.
or .03 mm.
Check circuit suction
pressure. If less than
-5 in. Hg., raise fluid level
in reservoir, clean intake
strainer and/or correct
faulty circuit design.
INSPECTION PROCEDURES Continued
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