Daewoo Solar 470LC-V, Руководство по ремонту

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S0302000
Page 4 General Maintenance Procedures
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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 components. Hoses that are 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 circuits are in neutral, or "OFF." That will prevent pumps or other components that
may be temporarily oil-starved from being run under a load.
Replacement of any hydraulic system component could require thorough cleaning, flushing, and some
amount of pre-filling with fresh, clean oil if the protective seal on replacement parts has obviously been
broken or if seal integrity may have been compromised. When protective seals are removed before
installation and reassembly, inspect all replacement parts carefully, before they are installed. If the
replacement part is bone dry (with no trace of factory pre-lube) or has been contaminated by dirt or by
questionable oils, flushing and pre-filling with clean hydraulic fluid is recommended.
Vibration, irregular or difficult movement or unusual noise from any part of the hydraulic system could be
an indication of air in the system (and many other types of problems). As a general precaution (and to help
minimize the risk of potential long-term damage), allow the engine to run at no-load idle speed immediately
after initial start-up. Hydraulic fluid will circulate, releasing any air that may have been trapped in the
system before load demands are imposed.
A daily walk-around pre-start equipment safety inspection, including a quick visual scan for any exterior
evidence of leaking hydraulic fluid, can help extend the service life of system components.
CAUTION!
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 hydrogen
embrittlement and structural weakening of the weld.
4. If welding procedures are being performed near cylinder rods, operator’s cab 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 through bearings, bushings, or spacers.
6. Always use correct welding rods for the type of weld being performed and observe
recommended 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.