Hydraulic System - General Precautions - Doosan DX140R Shop Manual

Observe the following safety precautions:
1. Use extra caution and adequate safety shielding when
welding near fuel and oil tanks, batteries, hydraulic
piping lines or other fire hazards.
2. Never weld when the engine is running. Battery cables
must be disconnected before the welding procedure is
started.
3. Never weld on a wet or damp surface. The presence of
moisture causes
structural weakening of the weld.
4. If welding procedures are being performed near
cylinder rods, operator's cabin window areas or any
other assemblies that could be damaged by weld
spatters, use adequate shielding protection in front of
the assembly.
5. During equipment setup, always attach ground cables
directly to the area or component being welded to
prevent arcing
spacers.
6. Always use correct welding rods for the type of weld
being performed
precautions and time constraints. AWS Class E7018
welding rods for low alloy to medium carbon steel
must be used within two hours after removal from a
freshly opened container. Class E11018G welding rods
for T-1 and other higher strength steel must be used
within 1/2 hour.
HYDRAULIC SYSTEM -
GENERAL PRECAUTIONS
Always maintain oil level in the system at recommended levels.
Assemblies that operate under heavy loads, at high speed, with
extremely precise dimensional tolerances between moving parts
- pistons and cylinders, or shoes and swash plates, for example
- can be severely damaged if oil supply runs dry.
Assemblies can be run dry and damaged severely in a very
short time when piping or hoses are disconnected to repair leaks
and/or replace damaged
inadvertently switched during disassembly (inlet for outlet and
vice versa), air introduced into the system or assemblies that are
low on oil due to neglect or careless maintenance, could all
produce sufficient fluid loss to cause damage.
When starting the engine (particularly after long layoff or storage
intervals), make sure that all hydraulic controls and operating
General Maintenance Procedures
CAUTION
hydrogen embrittlement
through bearings, bushings,
and observe recommended
components. Hoses
and
or
that are
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