Servicing; Hydraulic Pump (Power Steering And 3-Point Hydraulic System) - wsm STW37 Workshop Manual

STW34, STW37, STW40, WSM

[3] SERVICING

(1) Hydraulic Pump (Power Steering and 3-Point Hydraulic System)

Housing Bore (Depth of Scratch)
1. Check for the scratch on the interior surface of the housing
caused by the gear.
2. If the scratch reaches more than half the area of the interior
surface of the housing, replace at pump assembly.
3. Measure the housing I.D. where the interior surface is not
scratched, and measure the housing I.D. where the interior
surface is scratched.
4. If the values obtained in the two determinations differ by more
than the allowable limit, replace the hydraulic pump as a unit.
(Reference)
• Use a cylinder gauge to measure the housing I.D.
Depth of scratch Allowable limit
Clearance between Bushing and Gear Shaft
1. Measure the gear shaft O.D. with an outside micrometer.
2. Measure the bushing I.D. with an inside micrometer or cylinder
gauge, and calculate the clearance.
3. If the clearance exceeds the allowable limit, replace the gear
shaft and the bushing as a unit.
Factory specification
Clearance between
bushing and gear shaft
Allowable limit
Gear shaft O.D. Factory specification
Bushing I.D. Factory specification
Side Plate Thickness
1. Measure the side plate thickness with an outside micrometer.
2. If the thickness is less than the allowable limit, replace it.
Factory specification
Side plate thickness
Allowable limit
8-S21
HYDRAULIC SYSTEM
0.09 mm
0.0035 in.
9Y1211109HYS0036US0
0.020 to 0.081 mm
0.0008 to 0.0032 in.
0.15 mm
0.0059 in.
14.970 to 14.980 mm
0.5894 to 0.5898 in.
15.000 to 15.051 mm
0.5906 to 0.5926 in.
9Y1211109HYS0037US0
2.48 to 2.50 mm
0.0976 to 0.0984 in.
2.40 mm
0.0945 in.
9Y1211109HYS0038US0
KiSC issued 11, 2014 A