General Information; Description - Stiga 2021 Edition PARK 320 P Workshop Manual

WORKSHOP MANUAL
Summary
8.1 GENERAL INFORMATION ............................................................... 85
8.1.1
8.1.2
8.1.3
8.1.4
8.2 OPERATION OF THE HYDRAULIC SYSTEM ................................... 88
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.3 MAINTENANCE OF THE HYDRAULIC SYSTEM ............................. 94
8.3.1
8.3.2
8.4 DYNAMIC BALANCING VALVE (Smart by-pass) .......................... 97
8.4.1
8.4.2
8.4.3
8.5 HYDRAULIC DIAGRAMS ................................................................ 100
8.5.1
8.5.2

8.1.1 Description

Park machines with a two or four-wheel drive are equipped with a hydraulic transmission system,
consisting of an internal combustion engine that drives an hydraulic pump; the pump sends the
oil under pressure to the rear axle hydraulic motor (2WD models) and to the front axle hydraulic
motor (4WD models).
In the 4WD models, the front and rear units are connected in series, which means that the front
and rear wheel motors rotate at the same speed; to facilitate steering, both axles are equipped
with a differential.
All machines are equipped with an hydraulic steering valve (Booster) connected to the rear trans-
mission.
PARK
8 - HYDRAULIC SYSTEM
Description ................................................................................. 85
Safety criteria in the maintenance of the hydraulic system .......... 86
Diagram of hydraulic connections .............................................. 86
Configurations ............................................................................ 87
Components description and functioning ................................... 88
By-pass valves ........................................................................... 91
Hydraulic steering valve (Booster) .............................................. 91
Troubleshooting of the hydraulic system ..................................... 92
Troubleshooting of the hydraulic steering valve .......................... 93
Rear transmission unit filter replacement .................................... 94
System emptying and filling ........................................................ 95
Description ................................................................................. 97
Valve disassembly ...................................................................... 98
Valve calibration ......................................................................... 98
Park 4WD ................................................................................. 100
Park 2WD ................................................................................. 101

8.1 GENERAL INFORMATION

Chapter
8 - HYDRAULIC SYSTEM
EDITION PAGE
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