1. Radiator Surface Blockage

Engine overheating issues are often caused by blockages on the radiator surface. To increase heat dissipation area, radiators are equipped with cooling fins between the tubes. The small gaps between these fins can easily get clogged with willow catkins, mud, insect carcasses, and other debris. Once blocked, the airflow is insufficient, drastically reducing cooling capacity and causing the engine coolant temperature to rise too high. A thorough cleaning of the radiator can ensure it works optimally throughout the summer.

2. Internal Blockage of the Radiator

Nowadays, small rotary drilling equipment rarely uses water as coolant, so internal blockages in the radiator have become less common. However, some owners still prefer water, which contains a lot of minerals that can deposit inside the radiator as scale, affecting heat dissipation and leading to overheating. It's recommended to check for internal blockages by scale, and if there is a significant amount, take it to a radiator repair shop for cleaning and clearing.

3. Fan Clutch Failure

The role of the clutch fan is well known; it reduces the fan's speed when the coolant temperature is not high, reducing energy consumption to save fuel. However, if it malfunctions and maintains a low speed even when the coolant temperature is high, it will surely cause the engine temperature to rise. If your small rotary drilling equipment is overheating and other parts are fine, consider replacing the fan clutch.

4. Insufficient Tension of the Fan Belt

High engine temperatures caused by insufficient tension in the fan belt are easy to identify. If pressing the belt by hand feels slack, or if the belt slips and squeaks when accelerating, it indicates insufficient tension. Insufficient belt tension can lead to too low a speed of the fan and water pump, severely reducing cooling capacity and inevitably leading to high engine temperatures.

5. Incorrect Ignition Timing

With the advent of electronic control, high engine temperatures due to incorrect ignition timing have basically disappeared. However, on some older engines using mechanical pumps, overheating due to timing errors still occurs. If your small rotary drilling equipment uses a mechanical pump and is overheating, it's suggested to check if the ignition timing is within the normal range.

6. High Exhaust Back Pressure

Many might not know, but high exhaust back pressure can also lead to overheating. Generally, high exhaust back pressure is caused by two reasons: one is poor repositioning of the exhaust brake butterfly valve, leading to obstructed exhaust. The other is blockage inside the muffler or SCR catalytic converter, causing excessively high exhaust back pressure. Both can lead to high engine temperatures, reduced power, and increased fuel consumption.