CG938H Wheel Loader. Manual - part 26

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z  Besides the function of weakening the dangerousness of the explosion, the inflation with 

nitrogen may also delay rubber’s aging and gradually wear of tyres (it is especially 

important that the tyre has expected service life (four years above). In addition, it may 

red In tyre inflation, an inflation chuck that clips tightly automatically shall be used. 

The operator shall stand outside the tyre.   

z  The set pressure of the modulating valve of the inflation equipment shall not exceed the 

recommended pressure 300~340 kPa. The press of the tyre inflated with nitrogen shall be 

same as the one with air. Please consult with the tyre supplier for information on working 

pressure. 

 

1.2Regulation of Inflation Pressure 

z  If the loader works under a cold condition, the pressure for tyre inflation at a warm place 

of 18 ~21  is too low. The low pressure will shorten the service life of the tyre.

℃

℃

 

z  Please see working and maintenance manual for the regulation of inflation pressure under 

a cold condition. 

1.3 Purchase of Tyres 

The tyre’s specification is 23.5-25-20PR, tubeless.As the tyre requires to be replaced, the user 

may purchase the tyre of same specifications at the local store.

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II  Standard for Screw Torque

 

Usually, fasteners will be dismantled in repairing. For reinstallation, the following items 

shall be noted: 

z  The bolts and nuts dismantled from the loader shall be kept well for reinstallation. In case 

a new fastener is required, the size and grade of the new fastener shall be same as the old 

one. 

z  The strength of the material is marked with number (8.8, 10.9 etc.) on the head of the bolt 

usually. The standard torque for the 8.8-grade bolt and nut is given in the following table. 

 

 

the size of 

screw thread 

 

standard torque（N.m） 

M6 12±4 

M8 25±7 

M10 55±10 

M12 95±15 

M14 150±20 

M16 220±30 

M20 450±70 

M24 775±100 

M30 1600±200 

M36 2700±400 

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III  Daily Maintenance Guide

 

“Healthy examination” for the loader shall be conducted regularly or irregularly 

(examination and repairing). 

Causes of failure or lower performance of the loader shall be found out early and 

removed in time. In this way, a higher production rate and long service life may be attained. 

z 

Grease or oil accumulated on the loader will cause a fire. Therefore when the loader 

works for some time (about 1000 hours), the grease or oil on the loader shall be cleaned 

with steam or high-pressure water.

 

z 

Prior to maintenance, all joints, caps and blocks shall be wiped away.

 

z 

Examine leakage carefully. For any leakage, the leakage position shall be found out and 

repaired.

 

z  In case the leakage is suspected or found out, the liquid level shall be examined regularly. 

Caution 

In replacement of hydraulic components or pipes, the screw plug of exhaust valve 

on the hydraulic oil box shall be loosened so as to avoid the outflow of the oil in the 

hydraulic oil box. Upon the completion of repairing, the exhaust valve shall be fastened 

again, and then the engine may be started. 

z  The hinging part of the frame is the central unit connecting with the front and rear frames. 

Good lubrication of the hinging part can ensure the normal and safety operation of the 

machine. 

z  Regularly lubricate the pin of the rotating and hinging parts to extend the service life. 

z  Regularly examine whether all parts have any deformation, crack or abnormal factor. 

z  In hoisting, the lifting lug on the frame shall be used. Hoisting weak part and pin hole is 

not allowed so as to prevent them from damage. 

z  As the external power source is used to start the engine, please follow the explanation of 

“Starting of Engine” in the chapter of “Operation”. 

z  The machine has one 24kv starting system. Starting the engine with the external power 

source only can use the voltage of 24kv. High-pressure voltage will damage the electrical 

system. 

z  Examine the dust and foreign substances on the coarse filtering net. If necessary, the dust 

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and foreign substances shall be eliminated. Prior to discarding the coarse filtering net, 

clean it for six times. In cleaning the filter element, examine completely whether the 

filtered material has any crack. The filter shall be replaced once per year, even if the time 

of cleaning does not reach 6 times. As the coarse filter is repaired for three times, the thin 

filter shall be replaced. 

After installing a cleanly coarse filter, if the engine discharges black smoke, new fine 

filter shall be installed. 

Caution 

Do not try to repeatedly use the fine filtering element by means of cleaning. New 

one shall be used every time, or not the engine will be damaged possibly. 

Maintenance of Engine

 

In case the clauses relating to the maintenance of engine are not in conformity with the 

Engine Maintenance Manual, the Engine Maintenance Manual prevails.