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Concrete Pump Truck Engine Overheating in Summer: Causes and Solutions
Sep. 02, 2026
Concrete Pump Truck Engine Overheating in Summer: Causes and Solutions
During the hot summer months, high temperatures can place significant stress on the engine of a concrete pump truck.
When ambient temperatures remain high, the engine must continuously provide sufficient power while also supporting other vehicle systems, including the air-conditioning system. Under heavy workloads and extreme heat, engine overheating can become a common problem.
When the engine temperature rises above its normal operating range, typically around 80°C–90°C depending on the engine model and manufacturer, the engine may experience overheating, commonly known as “boiling over.”
So, what causes a concrete pump truck engine to overheat in summer? And how can operators diagnose and solve the problem?
1. Check the Engine Coolant
Coolant is an important medium for transferring heat away from the engine. It circulates through the engine cooling system and carries excess heat to the radiator, where the heat is released into the surrounding air.
If the coolant level is too low, the cooling system may not be able to remove heat effectively, causing the engine temperature to rise.
Operators should regularly check:
Coolant level
Coolant quality
Cooling system leaks
Radiator condition
Coolant hoses and connections
Important Safety Precaution
Never immediately open the radiator cap when the engine is hot.
A hot cooling system can be under significant pressure. Opening the radiator cap immediately may cause high-temperature coolant or steam to spray out and result in serious burns.
If the engine has overheated, shut down the vehicle safely and allow the engine and cooling system to cool sufficiently before inspecting or opening the cooling system. Follow the engine manufacturer's safety instructions.
Do not add cold water or coolant suddenly to a severely overheated engine unless specifically permitted by the manufacturer, as rapid temperature changes may damage engine components.
2. Check for Scale and Deposits Inside the Radiator
Excessive scale, corrosion deposits, or contamination inside the cooling system can reduce coolant circulation and heat-transfer efficiency.
Over time, deposits may accumulate inside the radiator and engine cooling passages, restricting coolant flow and reducing the radiator's ability to dissipate heat.
This can create a thermal insulation effect between the coolant and the radiator's heat-transfer surfaces.
If severe deposits are found, professional cleaning of the cooling system may be required. Depending on the condition of the radiator and engine cooling passages, specialized chemical cleaning or component replacement may be necessary.
For best results, cleaning procedures should follow the engine and radiator manufacturer's recommendations.
3. Use the Correct Engine Coolant
Using the wrong coolant can negatively affect engine cooling performance and long-term reliability.
Some operators may use tap water or ordinary purified water as a substitute for engine coolant. This is generally not recommended for long-term operation because proper engine coolant provides not only heat transfer but also corrosion protection and other cooling-system protection.
The coolant should meet the specifications recommended by the engine manufacturer.
Can Different Coolants Be Mixed?
Different coolant formulations should not be mixed unless the manufacturers specifically confirm compatibility.
Different coolant technologies may contain different additives. Mixing incompatible products can cause:
Precipitation
Corrosion
Deposits
Cooling passage blockage
Reduced cooling performance
Damage to cooling-system components
If the coolant type is unknown or contamination is suspected, the cooling system should be inspected and, where appropriate, flushed and refilled with the correct coolant.
4. Check the Radiator Fins and Cooling Surface
Concrete pump trucks and mixer trucks often operate in dusty construction environments. During driving and construction, the radiator and cooling fins can become covered with:
Dust
Mud
Oil
Leaves
Concrete-related debris
Other contaminants
When the radiator surface becomes blocked, airflow through the cooling fins decreases. This reduces heat exchange and can cause the engine coolant temperature to rise.
How to Clean the Radiator
After shutting down the engine and allowing it to cool:
Inspect the radiator and cooling fins.
Remove leaves and large debris manually.
Use compressed air to blow contamination away from the appropriate direction.
If necessary, use a low-pressure water stream for cleaning.
Use a soft brush carefully to remove stubborn dirt.
Avoid using a high-pressure water jet directly on the radiator fins.
Excessive water pressure can bend or damage the delicate cooling fins, reducing airflow and heat-transfer efficiency.
The exact cleaning direction and method should follow the vehicle manufacturer's recommendations.
5. Check the Thermostat
A faulty thermostat can also cause engine overheating.
The thermostat controls coolant circulation between the engine and radiator. When the engine is cold, the thermostat normally keeps the coolant in a smaller circulation loop so that the engine can reach its operating temperature more quickly.
As the coolant temperature rises, the thermostat opens and allows coolant to flow through the radiator for greater heat dissipation.
If the thermostat becomes stuck closed or fails to open properly, coolant circulation through the radiator may be restricted. As a result, engine temperature can rise rapidly, particularly under heavy load or in high ambient temperatures.
What Should You Do If the Thermostat Fails?
Do not simply remove the thermostat as a permanent solution.
Although removing a thermostat may sometimes increase coolant circulation under certain conditions, operating an engine without the correct thermostat can cause improper temperature control and may create other engine problems.
The safer approach is to:
Stop the vehicle safely if overheating occurs.
Allow the engine to cool.
Check the thermostat and cooling system.
Replace the faulty thermostat if necessary.
Have a qualified technician inspect the vehicle before returning it to heavy-duty operation.
Other Common Causes of Concrete Pump Truck Engine Overheating
In addition to the problems above, summer overheating can also be caused by other cooling-system or engine-related faults.
Cooling Fan Failure
The cooling fan plays an important role in maintaining airflow through the radiator, especially when the vehicle is operating at low speed or stationary on a construction site.
A damaged fan, faulty fan clutch, electrical problem, or control-system failure can significantly reduce airflow and cause overheating.
Water Pump Failure
The water pump is responsible for circulating coolant through the engine and radiator.
A worn or damaged water pump may result in insufficient coolant circulation, causing the engine temperature to increase.
Radiator Hose Problems
Cracked, swollen, collapsed, or leaking hoses can reduce coolant circulation or cause coolant loss.
All hoses and connections should be inspected regularly.
Low Coolant Level or Cooling System Leakage
A leaking radiator, hose, water pump, gasket, or connection can cause coolant loss.
If the coolant level repeatedly drops, simply adding more coolant is not enough. The source of the leak must be identified and repaired.
Excessive Engine Load
Concrete pump trucks may operate under demanding conditions for extended periods. High ambient temperatures combined with heavy engine loads can increase the cooling system's workload.
Operators should monitor engine temperature continuously and avoid prolonged operation when abnormal temperature increases are detected.
How to Prevent Concrete Pump Truck Engine Overheating in Summer
Regular preventive maintenance is one of the most effective ways to reduce the risk of engine overheating.
Before summer construction operations, operators should inspect:
Engine coolant level and condition
Radiator and cooling fins
Cooling fan
Thermostat
Water pump
Radiator hoses
Cooling system connections
Engine oil level and condition
Temperature sensors
Cooling system for leaks
During operation, the engine temperature should also be monitored continuously.
If the temperature rises abnormally, stop the equipment safely and investigate the cause instead of continuing to operate the pump truck under excessive temperature conditions.
Conclusion
Summer temperatures can place additional stress on concrete pump truck engines, especially during long hours of continuous construction.
Engine overheating may be caused by low coolant levels, radiator contamination, incorrect coolant, restricted coolant circulation, thermostat failure, cooling fan problems, water pump failure, or cooling-system leaks.
Regular inspection and preventive maintenance can significantly reduce the risk of overheating and help ensure reliable concrete pump truck operation.
For construction companies, choosing a reliable concrete pump truck manufacturer and following the manufacturer's maintenance recommendations are essential for maintaining equipment performance, extending service life, and reducing unexpected downtime.
JIUHE provides concrete pump trucks designed for demanding construction applications, with different boom lengths and configurations available for various project requirements.