jcb JS70 Service Manual

Travel - High Speed
During 2 speed travel the two step swash plate angle of
the travel motor is shifted to the minimum angle side
and 2 speed travel is initiated.
Pressurised oil is discharged from port A1(front
pump)and enters port 5P of the control valve.
Pressurised oil from port A2 (rear pump) enters port 4P
of the control valve. The pressurised oil is switched by
the left and right travel spools and flows to the travel
motor and travel occurs.
To achieve High speed travel, an electric signal is sent to
the High speed travel solenoid valve inside the multiple
valve by the travel switch. When the solenoid valve is
energised, 40 bar pilot original pressure from port A5 of
the multiple valve enters through port P5 of the left and
right hand track motors. It changes the swash angle of
the track motor to the minimum angle side engaging
High speed travel.
The electric signal from the travel switch is sent to the
monitor and illuminates the symbol.
3 - 4
Section E Hydraulics
9803/6020
Section E
3 - 4
Issue 1
Schematics
A
Pressure Lines
B
Return Line
C
Pilot line
D
Electric Signal
E
Travel Motor (Right)
F
Travel Motor (Left)
G
Rotary Coupling
H
Control Valve
J
Multiple Valve
K
Hydraulic Pump
L
Travel Change Switch
M
Monitor Display
N
Lamp goes on
P
Travel (R)
Q
Travel (L)

jcb JS70 Specifications

General

Brand	jcb
Model	JS70
Category	Excavators
Language	English