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HYDRAULIC SYSTEM
G23, G26, WSM
5-M6
(EU)
3. RELIEF VALVE
The hydraulic system circuit has a relief valve to
restrict the maximum pressure in the circuit. The relief
valve is located in the front case (1).
The relief valve is a guide piston type with damping
effect.
Among direct acting relief valves, this type is suited
to higher pressure and has large capacity. Furthermore,
this type is free from unstable operation, such as
chattering, which occurs often in direct acting relief
valves.
As shown in the figure, the guide is attached to the
poppet (3) and a valve chamber
D.C.
(called the
damping chamber) is formed at the top of the guide
piston. The inlet of the valve leads to the chamber via a
clearance between the sliding portion of the guide and
the seat (2), minimizing valve vibration with the damping
effect of the chamber.
9Y1210294HYM0006US0
Relief Valve Operating
When the oil pressure in the circuit is lower than the
setting pressure of the relief valve, the relief valve is not
operated and the oil fed to the relief valve from the
hydraulic pump flows into the hydraulic control valve.
When the pressure rises above the valve setting
pressure and overcomes the spring force, the relief
poppet opens. Oil then flows out to the transmission
case through
T
port, preventing any further rise in
pressure. The relief poppet closes again when enough
oil is released to drop pressure below the valve setting
pressure.
(Reference)
• Relief valve setting pressure
12.3 to 12.8 MPa
125 to 131 kgf/cm
2
1790 to 1850 psi
• Engine speed
1495 to 1505 min
-1
(rpm)
• Oil temperature
45 to 55 °C
113 to 131 °F
9Y1210294HYM0007US0
(1) Front Case
(2) Relief Valve Seat
(3) Relief Poppet
(4) Relief Spring
(5) Relief Valve
(6) Shim and Plain Washer
(7) Flow Priority Valve
(8) Line Filter
EF : EF Port (To Hydraulic
Control Valve and Mower /
Grass Collector Cylinders)
D.C. : Damping Chamber
P : Pump Port (Suction)
T : Tank Port
PF: PF Port (To Power
Steering, Hydraulic PTO
Clutch, and HST Circuit)
(1) Front Case
(2) Relief Valve Seat
(3) Relief Poppet
(4) Relief Spring
(5) Relief Valve
(6) Shim and Plain Washer
(7) Flow Priority Valve
(8) Line Filter
EF : EF Port (To Hydraulic
Control Valve and Mower /
Grass Collector Cylinders)
P : Pump Port (Suction)
T : Tank Port
PF : PF Port (To Power
Steering, Hydraulic PTO
Clutch, and HST Circuit)
KiSC issued 08, 2009 A
Summary of Contents for G23
Page 1: ...G23 G26 WORKSHOP MANUAL KiSC issued 08 2009 A ...
Page 3: ...I INFORMATION KiSC issued 08 2009 A ...
Page 9: ...INFORMATION G23 G26 WSM I 5 EU 9Y1210294INI0003US0 KiSC issued 08 2009 A ...
Page 10: ...INFORMATION G23 G26 WSM I 6 EU 9Y1210294INI0004US0 KiSC issued 08 2009 A ...
Page 11: ...INFORMATION G23 G26 WSM I 7 EU 9Y1210294INI0005US0 KiSC issued 08 2009 A ...
Page 15: ...INFORMATION G23 G26 WSM I 11 EU 4 DIMENSIONS LD 9Y1210294INI0007US0 KiSC issued 08 2009 A ...
Page 16: ...INFORMATION G23 G26 WSM I 12 EU HD 9Y1210294INI0008US0 KiSC issued 08 2009 A ...
Page 17: ...G GENERAL KiSC issued 08 2009 A ...
Page 81: ...1 ENGINE KiSC issued 08 2009 A ...
Page 149: ...2 TRANSAXLE KiSC issued 08 2009 A ...
Page 205: ...3 FRONT AXLE KiSC issued 08 2009 A ...
Page 216: ...4 STEERING KiSC issued 08 2009 A ...
Page 231: ...5 HYDRAULIC SYSTEM KiSC issued 08 2009 A ...
Page 266: ...6 ELECTRICAL SYSTEM KiSC issued 08 2009 A ...
Page 268: ...ELECTRICAL SYSTEM G23 G26 WSM 6 M1 EU 1 WIRING DIAGRAM 1 G23 KiSC issued 08 2009 A ...
Page 269: ...ELECTRICAL SYSTEM G23 G26 WSM 6 M2 EU 2 G26 KiSC issued 08 2009 A ...
Page 308: ...7 MOWER KiSC issued 08 2009 A ...