2) Check the temperature difference between the inlet and outlet water pipes, and check the inlet temperature:

 

What are the reasons and solutions for the high exhaust temperature caused by the malfunction of the thermal control valve? Reason analysis: There is a thermal control valve (temperature control valve) at the front end of the oil cooler. If the oil temperature rises to the opening temperature, the thermal control valve will gradually open until fully open. At this time, the lubricating oil will cool down through the oil cooler before entering the machine body. When it fails, the lubricating oil will not pass through the oil cooler, so the temperature will slowly rise and the machine will shut down. The common cause of malfunction in the operation of thermal control valves is jamming due to carbon accumulation. Treatment method: Clean or replace. Generally, the core of the thermal control valve can be removed and cleaned with a carbon cleaning agent. The test method can be to place the valve core in hot water to check if it operates normally.