LG956 Wheel Loader. Service manual - part 26

Operation & Maintenance Manual──LG956L Wheel Loader 

 103

 

3.8.5  Steering System 
 

No. Problems 

Possible 

Causes 

Remedy 

1 

Heavy steering 

1  Insufficient oil supply for working pump 

and steering pump 

2  Air in steering system 
3  Faulty steel-ball in check valve body of 

steering unit causes heavy steering and 
little pressure during either slow or quick 
turning of steering wheel 

4  Faulty of piloted valve 
5  Too low pressure of safety valve 

1  Check oil pump 
2  Discharge air from system and 

check the suction lines 

3  Check the valve. Clean if it is 

blocked by dirt 

4  Replace piloted valve 
5  Readjust the pressure to 

specified value 

2 

Increased 
steering turns 

1  Insufficient oil level in hydraulic reservoir 
2  Leakage in oil lines, damaged oil seals 
3  Internal leakage of steering cylinder 
4  Worn steering unit 
5  High viscosity of oil or wrong brand of oil 

1  Fill oil to specified level 
2  Change seals of oil circuits 
3  Change seals of hydraulic tanks 
4  Replace steering unit 
5  Change by the specified oil 

3 

Inflexible or 
failure of 
steering system 

1  Damaged spring plate of steering unit 
2  Cracked, broken or deformed centre pin 

and drive shaft 

3  Faulty dual overload valve 
4  Scuffed rotor and stator, scuffed valve 

spool, valve body and sleeve 

5  Faulty in steering pump or piloted valve 

1  Change the damaged spring 

plate 

2  Change the center pin or drive 

shaft 

3  Check and repair the 

bi-directional overload valve 

4  Disassemble, check, clean and 

assemble strictly or change parts

5  Change the damaged parts 

4 

Steering wheel 
can not reset 

1  No concentric steering column and valve 

spool 

2  Steering shaft axially locks the valve plug 
3  Large axial resistance of steering column 
4  Broken spring plate 

Phenomena: medium pressure drop 
increases or the relief of steering unit fails 
when steering wheel stops (wheel loader 
deflects from straight traveling line) 

Remove the problems according to 
the respective reasons. 

 

3.8.6 Engine 

Refer to 

Operation and Maintenance Manual 

of diesel engine for troubleshooting. 

 

 

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CHAPTER  

MAINTENANCE

Ⅳ

 

1 MAINTENANCE GUIDE 

Read following information carefully before carrying out maintenance and inspection. 

1.1 Attention to Maintenance and Inspection 

z  Perform the maintenance on hard and level ground. 
z  Lower the work equipment near the ground and level the bucket. 
z  Set all control levers to the Neutral position. 
z  Draw up the parking brake handle to set the loader in the parking brake state. 
z  Put blocks in the front and back of wheels. 
z  Lock the front and rear frames with frame locking bars. 

1.2 Hanging Warning Tag 

z  Attach the warning tag near the starting switch before maintenance to prevent someone starting 

the engine during maintenance. 

1.3 Fitting preparation 

z  Use only parts specified by the manufacturer of the loaders wheel. 

1.4 Oil and Fuel preparation 

z  Use oil and fuel specified in this manual according to ambient temperature. 

1.5 Using the Prescriptive Oil and Fuel 

z  Keep containers of oil and fuel clean and use specified oil and fuel. 

1.6 Keep the Machine Clean 

z  Always keep the machine clean. Keep grease fittings, pipe joints and oil level gauges clean and 

prevent foreign materials entering. 

1.7 Pay Attention to the Refrigerant Water and Oil in High Temperature 

z  It is very dangerous to drain hot oil and refrigerant water or remove the filters immediately after 

the engine stops. Make sure the engine is cool. The temperature of the oil drained is appropriately 

about 20  to 40

℃

℃

. If it is lower than this temperature, be sure to warm it up to this temperature 

Operation & Maintenance Manual──LG956L Wheel Loader 

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before draining it. 

1.8 Check the Oil and Filters 

z  After the oil is changed or filters are replaced, check the oil and filters. If large amounts of 

metallic particles or impurities are found, consult the maintenance people. 

1.9 Fuel Strainer 

z  Do not remove the fuel strainer while fueling. 

1.10 Oil Changing 

z  Change oil in relationship dust-free places to keep impurities out of the oil. 

1.11 Welding Guide 

z  Turn off the starting switch of the engine and remove the battery cables. 

z  Keep the distance between the grounding cable line and welding area more than 1m. 

z  Avoid welding near the seal rings and bearings. 

z  Never weld any pipe or tube while has fuel as or oil in them. 

1.12 Fire Prevention 

z  Clean the parts with inflammable cleaner or light oil. Keep spark or cigarette light away from 

them. 

1.13 Sealing Part 

z  When replacing O-ring or gaskets, clean the clamp faces first, and make sure the O-ring and 

gaskets are in the correct assembly position. 

1.14 Checking the Frame 

z  After a long time of operation in rocky conditions, check for damage of the undercarriage and 

loose or damaged between bolts and nuts. 

1.15 Attention to Washing Machine 

z  Wash machine after complete cooling of the engine. 

z  Do not allow water to spray on any electric components. 

1.16 Checking in Raining and Snowing Circumstances 

z  Clean the machine immediately after working in rain and snow. Lubricate and coat anti-rust oil to 

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other parts. 

1.17 Dusty Circumstances 

Do the following when the machine works in dusty circumstances: 

z  Inspect and clean air filter frequently to avoid blocking. 
z  Clean the radiator frequently to avoid blocking. 
z  Clean and replace fuel filter frequently. 
z  Clean the electric components, especially the starting motor and alternator, to avoid accumulation 

of dust affecting dispelling heat. 

z  Refer to 

Operation and Maintenance Manual

 of diesel engine for replacing and 

maintaining air filter. 

1.18 Avoid Using Mixed Oil 

z  Never use oil mixed from different brands. If only a different kind of oil from the one previously 

used, drain the oil from the machine, and fill with the new brand oil. 

 

2. DETAILED RULES OF MAINTENANCE 

2.1 Detailed Rules of Using Oil, Fuel and Coolant 

△

!

 

WARNING

 

z  Because of bad operating conditions (high temperature and high load) 

and dusty ambient circumstances, oil easily deteriorates. Change oil 

as soon as the oil deteriorates or is mixed with many impurities. 

z  Add the specified volume of oil. Either too much or too little oil may 

cause problems. 

z  Clean and replace the relative filters when changing oil. 

 

2.1.1 Fuel 

z  The fuel pump is a precision instrument. If the fuel mixes with water or dirt, the fuel pump will 

not work normally. 

z  Never let impurities enter when changing and adding fuel. 

z  Strictly choose the fuel brand according to this manual. 

z  The fuel may be frozen at low temperatures (particularly temperatures lower than -15 ). So it is 

℃