Hst Pump - Komatsu WA250-6 Shop Manual

SEN03826-00

HST pump

a HST: Abbreviation for HydroStatic Transmission
1. Directional selector solenoid valve
2. High-pressure cutoff valve
3. Speed-related valve (DA valve)
4. Charge pump
5. Low-pressure relief valve
6. Servo cylinder
7. High-pressure relief valve
8. Control plate
9. Cylinder block
10. Piston
11. Swash plate
8
10-200
Specifications
Model name
Type
Theoretical delivery
(cc/rev)
High-pressure relief valve
set pressure
(MPa {kg/cm })
2
High-pressure cutoff valve
set pressure
(MPa {kg/cm })
2
Low-pressure relief valve
set pressure
(MPa {kg/cm })
2
200 Power train

HST pump

A4VG90DA
Variable displacement
swash plate type piston
pump
0 – 90
44.1 {450}
Effective differential
pressure
41.2 {420}
2.45 {25}
WA250, 250PZ-6
1