Expansion tanks
The Role of Expansion Tanks in the Cooling System
In this section of the Enrique Requena online catalogue, you will find a wide selection of expansion tanks specifically designed for heavy-duty and commercial vehicles. These components are essential for balancing internal pressure and managing coolant volume variations caused by temperature changes during engine operation.
Our range is aimed at professional workshops and fleet managers who require compatible spare parts for maintaining the thermal circuit. Having an intact, crack-free expansion tank is vital to prevent coolant loss, avoid overheating and facilitate visual inspection of fluid levels during routine maintenance checks.
Criteria for choosing the correct expansion tank
- OEM reference: Verify that the part number matches the vehicle manufacturer’s original reference to ensure a perfect fit.
- Model compatibility: Make sure the tank is suitable for the make, model and year of the truck or industrial vehicle.
- Connections and sensors: Check the number of inlet/outlet nozzles and whether the tank includes or supports the coolant level sensor.
- Manufacturing material: The plastic must be resistant to high temperatures and constant pressure without deforming.
- Cap inclusion: Review the technical sheet to confirm whether the replacement includes the pressure cap or if it must be purchased separately.
Frequently Asked Questions
What is the main function of the expansion tank?
Its function is to absorb excess coolant that expands when the engine heats up and return it to the radiator when it cools down. It also acts as a bleed point to remove air bubbles from the system and allows the circuit to be easily refilled.
When should I replace the expansion tank of a heavy-duty vehicle?
Immediate replacement is recommended if cracks in the plastic are detected, leaks at the seals appear, or if the material has turned yellowish/opaque, making the fluid level difficult to see. It should also be replaced if the material has become brittle due to continuous thermal cycles.
Do replacement tanks include the level sensor?
This depends on the specific product reference. Some models are supplied complete with the level sensor pre-installed, while others include only the plastic tank, requiring reuse of the old sensor or purchase of a new one. Please consult the product description.
Is any cap compatible with the new tank?
No, the cap must be rated to the specific pressure required by the vehicle’s cooling circuit. Using a cap with incorrect pressure may cause leaks due to overpressure or prevent the system from reaching the proper operating temperature.
