In the hot summer, the high temperature can make us very uncomfortable and even suffer from heat stroke. The same is true for trucks, which can overheat in some cases and affect normal driving, especially semi-trucks used for long-distance transportation. There are several common causes of heavy truck overheating, and troubleshooting and fixing these issues can prevent damage caused by overheating trucks. This article will list 7 common causes of heavy truck overheating due to cooling system failure and other conditions, and provide some solutions for each problem.
Truck Overheating Due to Cooling System Failure
The cooling system plays a vital role in preventing the truck from overheating. The cooling system is composed of radiator, cooling fan, thermostat, water pump, compensation bucket and other accessories. A problem with any one of these devices could cause the truck to overheat. Here are 5 possible causes and solutions for your truck to overheat due to a malfunctioning cooling system:
1. Radiator Surface Clogged
One of the most common causes of a truck overheating is a clogged radiator surface. Because radiators require a lot of air to dissipate heat, the surfaces need to be kept clean. However, due to the relatively narrow design of the cooling hole, it is easy to be blocked by catkins and other sundries. At this time, you can use a high-pressure water gun to rinse the surface of the radiator. When flushing, be sure to adjust the nozzles to spray in a dispersed state to reduce the water pressure and avoid damage to the radiator.
2. Radiator Internal Clogged
Because today’s trucks rarely use water as a coolant, it is rare for the radiator to become clogged. But some drivers still prefer to use water. This can cause limescale to build up inside the radiator, which can clog it and reduce heat dissipation. Therefore, trucks using water-cooled heat dissipation systems try to use special antifreeze or soft water (water that does not contain or contains less soluble calcium and magnesium compounds) as a coolant. If your truck has been using tap water as coolant and is experiencing a situation where your truck is overheating, it is advisable to check for blockages inside the radiator. If scale accumulation is found, you need to go to a professional repair shop to clean and dredge it.
3. Cooling Fan Failure
The cooling fan can control the fan speed according to the engine temperature to speed up the heat dissipation of the radiator. It plays a key role in reducing engine temperature.
In addition to causing the engine to overheat, the failure of the cooling fan will also affect the normal operation of the thermostat and radiator. In order to prevent greater losses, please replace the cooling fan of the truck in time.
4. Insufficient Fan Belt Tension
Insufficient fan belt tension can also cause diesel engines to overheat. The tightness of the fan belt can be easily checked by pressing with your hand. If you feel slack or if you hear the belt slipping and squeaking when you step on the accelerator, the belt tension is insufficient. In this case, the fan belt needs to be tightened to ensure the normal operation of the fan and water pump to dissipate heat effectively.
5. Thermostat Failure
The thermostat is responsible for controlling the temperature of the engine coolant within a reasonable range. If the thermostat fails, it will not open when the temperature exceeds the rated temperature, or the opening will be small, which will cause the engine temperature to be too high. If you experience engine overheating while driving, be sure to check that the thermostat is working properly. But it is not recommended to remove the thermostat. Because this may cause the engine temperature to become uncontrollable, resulting in high fuel consumption and increased wear and tear.
Other Causes of Truck Overheating
When troubleshooting the cause of a heavy truck overheating, there are other places to look besides the cooling system. These conditions can also cause your truck to overheat:
1. Wrong Ignition Timing
Older engines with mechanical pumps can cause trucks to overheat due to incorrect ignition timing.
At the end of the compression stroke of the engine and the piston reaches the top of the stroke, the ignition system provides high-pressure sparks to the spark plug to ignite the compressed mixture in the cylinder to do work. This time is the ignition timing.
In order to maximize the ignition energy, the ignition timing is generally advanced by a certain amount. So the ignition is fired at the moment when the piston is about to reach top dead center, not just when it reaches top dead center.
If your truck is a mechanical pump and you are experiencing diesel overheating, don’t forget to check that the ignition timing is within the normal range.
2. High Exhaust Back Pressure
Another lesser known cause of overheating trucks is high exhaust back pressure.
Exhaust back pressure refers to the resistance pressure of engine exhaust. When the exhaust back pressure increases, the exhaust of the engine is not smooth, which affects the power of the engine.
When the exhaust back pressure is too high, the fuel consumption rate of the engine will directly increase, and the economic performance of the engine will deteriorate. At the same time, the power performance of the engine will also deteriorate and the temperature will increase.
This happens when the exhaust brake butterfly valve does not close properly resulting in poor exhaust flow, or when the muffler, SCR catalytic converter becomes clogged internally. If it is found that the truck is overheated due to high exhaust back pressure during the investigation, it is necessary to repair or replace the catalytic converter in time.
There are far more than these 7 causes of heavy truck overheating, these are just a few of the most common. In addition to the reasons of the truck itself, improper operation can also cause the truck to overheat. Therefore, when encountering such problems, it is necessary to carry out systematic inspections and not to repair them blindly. Because the truck is a whole, if there is a problem in any link, it will cause different or similar failure performances.