How to maintenance isuzu truck

Common Failure and Troubleshooting

Oil leakage happened on oil cylinder piston rod    
1、The damage of the sealing ring


2、There are scars on the surface of the piston rod
    
1、Carefully exam the guide sleeve and replace the sealing ring

2、Replace the parts.


Piston rod move slowly   
1、Some air mixed in the hydraulic cylinder or in the hydraulic oil

2、There are no hydraulic oil in the tank or oil level is too low to work normally.

3、Viscosity of hydraulic oil failing standard

4、Stoppage of the oil inlet/outlet strainer


5、Stoppage or limiting of the hydraulic oil in system

6、Leakage of the oil suction pipe

7、Abrasion of the oil pump

8、Abrasion of some parts

9、Adjustment of the parts are not proper.

10、Pressure valve is too dirty

11、Overload of the system work

12、Improper oil pipe connection

13、Oil pump not work

14、The hydraulic oil temperature is too low


15、The engine’s revolving speed is not enough
    
1、Eliminate all the air



2、Inject some hydraulic oil and carefully check the system.

3、Replace hydraulic oil to recommended ones.

4、Carefully clean or replace it, and find out the polluted reason

5、Carefully check the oil pipes and clean them.

6、Repair or replace it


7、Repair or replace it

8、Carefully check the pump, valve and oil cylinder, find the abrasion part and repair or replace it.

9、Refer to the technical manual to adjust properly

10、Carefully clean it

11、Refer to the technical manual to load properly.

12、Reconnect the oil pipe properly

13、Carefully check the PTO

14、The viscosity is too high and should be adjust oil temperature to working level

15、Adjust to proper level


Hydraulic cylinder pushing is powerless   
1、Damage of the piston sealing

2、System pressures is too low (the overflow valve became imbalance)

3、Damage of the oil pump, System pressures is too low

4、Shortage of the hydraulic oil

5、Stoppage of the oil filter
    
1、Carefully exam and replace the sealing element

2、Carefully exam and adjust the pressure of the overflow valve

3、Carefully exam and replace the oil pump

4、Carefully exam and fulfill the hydraulic oil

5、Carefully exam and replace the filter element


Leakage of the oil pump   
1、Damage of the sealing filter

2、The oil pipes are not sealed as required   
1、Carefully exam and replace the sealing ring

2.1、Carefully exam, tighten the joint
2.2、Replace the joint or add some sealant to seal the joint


Blister exist in the hydraulic oil   
1、Oil level in the tank is too low


2、There is water in the hydraulic oil

3、Leakage of the pipe between the oil tank and the pump

4、Hydraulic hose is kinked or squished, and limit the flow of the oil

5、Have not choose the right hydraulic oil

6、Abrasion of the sealing parts in oil pump axle
    
1、Adjust the oil to required level. Carefully exam the leakage of the system.

2、Exchange new hydraulic oil

3、Fasten the joint or exchange suction pipe

4、Replace the oil pipe

5、Exchange to the recommend oil

6、Carefully clean or replace it.

Oil pump is too noise while working    1、The hydraulic oil viscosity is too high

2、Speed of the oil pump is too high

3、Suction pipe is blocked or extrusion

4、The oil tank’s respirator is blocked

5、Primary oil filter is blocked

6、Parts sticking to each other



7、There are air in the hydraulic oil


8、Hydraulic oil level is too low

9、Parts of the oil pump is abrasion
    1、Change low viscosity oil

2、Adjust the oil pump’s speed to required level.

3、Cleaning or exchange the suction pipe

4、Open the respirator , Carefully wash to clean it.

5、Cleaning the filter screen

6、Carefully repair the sticking parts, cleaning all of them, and replace when necessary

7、Carefully check the system, replace the suction pipe and sealing parts.

8、Adjust to proper level


9、Repair the oil pump and find out the reason


Leakage of oil cylinder   
1、Damage of the cylinder


2、Damage of the parts of piston valve

3、Parts of the oil cylinder is loose

4、Damage of the piston rod
    
1、Replace the cylinder and find out why it damaged

2、repair or replace the piston valve, find out the reason

3、Fasten the parts until no leakage

4、Carefully exam, exchange it when necessary


Hydraulic oil temperature is too high   
1、Use the control valve for a long time

2、Hydraulic oil is not proper

3、The revolving speed is high

4、The inside leakage   
1、The manual joystick should reposition when not use

2、Exchange to proper oil

3、Adjust to proper level

4、Carefully check the pump, valve and oil cylinder to find out reason, then repair it.