All Copyright and rights are the property of Johnston Sweepers Ltd
V Range 501
l
651
l
801 Maintenance Manual
MA2:2
Chapter - Hydraulic System
General Description
The hydraulic system may be divided into four hydraulic circuits fed from a common hydraulic reservoir.
1 Sweep system and load discharge. (VT and VS)
2 Options system for Supawash etc. (VT and VS)
3 Fan Drive (VS Only)
4 Transmission system. (VS Only)
Hydraulic filtration is provided by suction filters within the hydraulic tank, together with replaceable type
‘in line’ return filter mounted externally on the upper face of the hydraulic tank.
• Do not remove any hydraulic components without first ensuring that any residual pressure
has decayed. If in doubt ask.
• Only competent trained personnel should work on this equipment.
Safety Notice
Page Issue A
HYDRAULIC SYSTEM - INTRODUCTION
Test points
Test points are provided on the hydraulic system to carry out pressure checks.
Identification
Function
Machine
Type
H -15Z6
Boost pressure, Reverse pressure and Antiskid
VS
H
-15Z7
Pump
control
pressure
VS
H -15Z3
Boost pressure, Forward pressure
VS
H
-15Z2
Boost
pressure
VS
H
-15Z5
Motor
control
pressure
VS
H
-15Z7
Coast
pressure
VS
H - 1Z2
Sweep system
VT & VS
H
-13Z5
Fan
drive
system VS
H -12Z2
Options system i.e. Supawash
VT & VS
H - 8Z2
Discharge functions
VT & VS
H -1472
Rear Wanderhose/Powaboom
VT & VS
Body Discharge System
To set system pressures, select option 12 from the main menu.
System Pressure:
Select option 1 from menu 4.12 and follow the on screen prompts:
Connect a suitable 250 bar gauge to test point H-8Z2 on the discharge system block on the LH side of
the machine. Once connected, acknowledge this by pressing the rotary encoder on the display.
Start the engine and run at the appropriate speed and acknowledge by pressing the rotary encoder on
the display.
Check pressure and adjust if required relief valve H-8V3 on the discharge system block to 190bar.
Acknowledge the pressure is set by pressing the rotary encoder on the display.
Do not run the pressure test for more than 30 seconds.
CIRCUIT PRESSURES
