What causes CV cooling radiator failures?
Highway Automotive explores CV cooling radiator failures, what causes them, what to look for and what to do.
Engine cooling is a vital requirement for all internal combustion powered commercial vehicles and it is typically achieved with the use of a liquid coolant that is circulated around the engine via a closed system. The coolant gets hot as it absorbs the heat generated by the engine as it flows around its water jacket and is subsequently cooled by passing through a radiator. Therefore, any problems with the radiator can have catastrophic consequences on the engine and the overall reliability of the vehicle.
There can be several reasons for radiator failure, but generally they are caused by external factors rather than because the radiator itself is defective. However, whatever the cause – coolant leaks, restricted flow etc. – the result will significantly affect engine operation and may lead to its failure.
Common radiator problems, symptoms and root causes
Corrosion: leaks and restricted coolant flow
Aluminium powder and rust deposits at the radiator header plate, inside the radiator or at the inlet and outlet are likely to be caused by either the improper coolant, i.e., tap water/dirty water, or reused antifreeze. In addition, mixing different kinds of antifreeze, or not having the correct coolant mixture can also have similar consequences. External corrosion can also be a problem in areas subject to high levels of saline in the atmosphere, such as in coastal regions, or where there is a high use of road salt.
Debris/deposits inside tubes: leaks and restricted coolant flow
Contamination such as scale, jelly-like substances or other debris/particle concentrations inside the coolant channels can again be caused by using the wrong coolant or coolant mixture but can also be because of a failure to flush or improper flushing of the system prior to radiator replacement.
Surface soiling: insufficient heat exchange
If the surface of the radiator is covered by contaminants, the air flow through its fins will be restricted and this will reduce its cooling efficiency. Likely causes include a lack of general vehicle maintenance, prolonged periods when the vehicle has not been used, oil/coolant leaks that cause the surface to become sticky and so attract debris/contaminants that cannot disperse during the normal use of the vehicle.
Electrolysis: leaks and restricted coolant flow
Visible white powder inside the radiator or at its header plates, or greenish colours around fins and tubes can be a result of a fault with the vehicle’s electrical system causing a current to affect the cooling system by initiating an electrochemical reaction.
System over-pressure: blown or burst tanks/radiator tubes
Visible bursts or deformation of the radiator or related parts can be caused by a defective radiator cap, restricted flow within the expansion tank, a blown engine head gasket or improper coolant (its boiling point is too low) and are likely to result in coolant leaks.
Broken radiator threads
Leaks/loose couplings within oil cooler fittings (if integrated with the radiator), coolant sensor sockets, drain plugs can be caused by screw threads that have been stripped or damaged due to careless or improper service. This will naturally lead to coolant leakage.
Mechanical damage: broken/bent tubes or cracked tanks
Visible surface or element damage can result in restricted flow rates and coolant leaks and are often caused by careless handling during transportation, or because of a collision with another vehicle or some other unyielding object.
Recommended solutions
Inspect the radiator surface, cap, expansion tank and ducts on a regular basis. Use solely the coolant specification/coolant mixture prescribed by the vehicle manufacturer.
Before installing a new radiator, a thorough inspection to establish what caused the previous part to fail is required for the root problem to be identified beforehand. Once that objective has been achieved, the following specific actions must be undertaken:
- the entire cooling system must be flushed
- inspect the vehicle’s electrical system and make sure the cooling system is not exposed to/in contact with a faulty current
- inspect the radiator cap, expansion tank and ducts, and ensure the engine head gasket is intact
- inspect the oil cooler connection (if applicable) and make sure the oil circuit is not over-pressured
About highway automotive
For more than 15 years, Highway Automotive has been honing its expertise in the manufacture of heating, cooling, and efficiency system replacement parts for the truck, bus, construction and agricultural sectors. The company’s deep understanding and comprehensive knowledge has allowed it to constantly exceed customer expectations and to be not only the first-choice brand, but also the only one needed.
In addition, always handle the replacement radiator with proper care. It is fragile and elements such as its mounting brackets, inlet/outlet and drain plugs, which often stick out, can easily get broken in transport or during the installation process.
