Takeuchi TL150, Руководство по ремонту

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IV-25
HYDRAULIC UNITS
HST PUMP
INSPECTION AND ADJUSTMENT
Checking the Parts
If abnormal components are found, never reuse
them; always replace with new ones.
Cylinder Block
• The sliding surface or the surface that contacts
the valve plate must be smooth and free from any
damage or burrs.
• The flatness of the sliding surface of the cylinder
block must be 0.000079 in. (0.002 mm) TIR.
• The maximum diameter of the cylinder bore must
be 0.635 in. (16.14 mm), and the minimum height
of the cylinder block must be 2.200 in. (55.88
mm).
Piston and Slipper of the Cylinder Block
• Place a sheet of white paper behind the piston to
see if there is any discoloration on the piston. If
there is, it shows that the piston has been exposed
to extremely high temperature.
• The slipper must not be damaged or worn ex-
cessively, and its edge must not be worn exces-
sively.
• The slipper clearance must be 0.006 in. (0.152
mm) or less.
Valve Plate
• The thickness (A) of the valve plate must be at
least 0.152 in. (3.86 mm).
• The sliding surface and the rear surface must be
smooth.
• The parallel accuracy must be at least 0.00098 in.
(0.0249 mm).
• The flatness of the valve plate must be 0.00015 in.
(0.0038 mm) TIR.
• Perform the magnetic particle inspection (nonde-
structive testing) to see if there is any cracking.
No cracking must be found on any surface.
• Inspect the seal land surface for damage by touch-
ing it with a prong such as the tip of a nail or pen-
cil and by moving it in the direction of diameter.
• Check if there is any contamination on the surface
where the valve plate and the housing contact.
Even slight contamination can cause reduced
flow rate.
Servo Cover
• The servo cover
·
s surface that contacts the gasket
must be clean and smooth.
• No scratch or foreign matter should be allowed on
the surface.
S3F330E
Minimum cylinder
block height :
2.200 in. (55.88 mm)
Running face flatness : Flat to 0.000079 in. (0.002 mm)
S3F331E
Maximum end play : 0.006 in.
(0.152 mm) or less
Slipper
Minimum slipper
foot thickness :
0.145 in. (3.68 mm)
Piston
S3F332E
Minimum thickness : 0.152 in.
(3.86 mm) or less
A
S3F333E
Sealing land
surface