Maintenance knowledge - bulldozer engine cooling water temperature alarm

Maintenance knowledge - bulldozer engine cooling water temperature alarm

Model: Bulldozer

Working environment: earthwork

Fault: Engine cooling water temperature alarm

Fault Symptom:

The customer called to feedback that the engine cooling water temperature alarm fault code appeared in the instrument many times when the vehicle was working, and the water temperature was as high as 103 °C, and the equipment could not be used normally.

Fault checking:

When the service personnel arrived at the site for testing, they found that the fault phenomenon did exist, which was the same as the fault described by the customer. The equipment is then inspected by the service personnel:

1. Start the vehicle and check that the engine cooling water temperature displayed by the vehicle instrument is up to 103°C. After the engine is turned off, wait for 15 minutes, wait for the engine temperature to come down, check that the engine water level is normal, check that the water temperature sensor is not loose, and check that the engine thermostat and belt
 tension are normal.

2. Subsequently, the service personnel inspected the radiator and found that the radiator fins were not damaged, there was no debris blockage, and the water tank was not found to be leaking, and there was no poor contact or loosening.

3. Due to the normal operation of all components of the vehicle cooling system, it is suspected that the design problem of the engine thermal balance system may be caused by the low speed of the fan.

Failure Analysis:

After consulting the relevant technical personnel of the factory, due to the normal operation of all components of the vehicle cooling system, it is suspected that the high temperature of the engine cooling water is caused by the low speed of the fan, resulting in low engine heat exchange efficiency.

Troubleshooting:

After consulting the relevant technical personnel of the factory, it is recommended that the SD32 bulldozer be replaced with fan belts and pulleys to increase the fan speed and improve work efficiency.

Remark:

Due to the limitation of the equipment structure, the original pulley was made smaller. Increase the fan speed to change the air volume and air flow rate, speed up air convection, and enhance the heat dissipation capacity of the radiator. After improvement, after testing, the water temperature dropped from the original 103 degrees to the normal temperature of about 83 degrees. And the temperature measurement of 15 position points of the water tank cooling system is carried out, which has obvious effects.