Dayco presents best practices for water pump replacement

The water pump is a crucial component of any internal combustion engine. Its function is to circulate coolant, which helps maintain the engine’s optimal operating temperature. Improper operation of the water pump can lead to serious failures, so it is very important to inspect it regularly. It is also important to follow best practice when replacing it.

In many applications, the water pump is driven by the timing belt. This means that its proper functioning is even more critical. Therefore, it is recommended to replace the water pump with each timing belt replacement.

To ensure a successful water pump replacement, here are some examples of best practices to follow when installing a water pump.

Ensure the cooling system is clean before installing the new pump

Before replacing the water pump with a new one, carefully inspect the removed part. It may show signs of deposits or corrosion, indicating the presence of contaminants or too much water in the cooling system. It is crucial to always flush the entire system before adding new coolant. If this is not done, dirt in the system can quickly enter the pump seals, causing damage and leakage.

Ensure proper pump sealing

Before installation, thoroughly clean and dry the mounting surfaces. Pay attention to the pump manufacturer’s instructions regarding bolt torque setting and correct belt tension.

A common installation mistake is to use silicone or sealant on the seal between the water pump and engine block. This can cause these substances to get into the pump impeller and damage its seals. Always follow the installation instructions supplied with the pump.

Do not allow the pump to run dry

The internal seal of the water pump requires contact with coolant to function properly. During pump operation, the coolant gets between the internal sealing rings, which rotate relative to each other and act as a seal. Running the pump dry can damage these sealing rings, causing leaks later.

To avoid this, after replacing the pump, fill the cooling system with coolant and turn the pump pulley several times by hand before fitting the drive belt. This will ensure that a small amount of coolant reaches the sealing rings. Another method is priming the water pump in coolant before installation. Never start the engine with a dry pump. Check for leaks only after the entire timing system has been assembled.

Ensure that the belt is properly tensioned

In most vehicles, the water pump is driven by the timing belt. The torque is transmitted to the pump via a pulley connected to the pump shaft and integrated with a bearing. Incorrect belt tension can damage the internal components of the pump.

If the belt is too tight, the shaft will transmit too much torque, accelerating bearing wear. Conversely, a belt that is too loose can cause slippage, which affects the high temperature of the pulley. The heat transferred to the bearing accelerates the wear of the grease. Without proper lubrication, the bearing will quickly degrade.

Remember that the timing system is an integral circuit in which all the components must work together perfectly. One damaged or improperly installed part could affect the functioning of the entire system.

Use the correct type of coolant

Water pumps are not designed for use with ordinary water. Always use the coolant recommended by the vehicle manufacturer. Be careful when mixing coolant from concentrate. The use of hard water can contaminate the coolant with calcium and magnesium deposits. It is best to use de-ionised water. Distilled water is also unsuitable as it changes its pH to acidic when heated, which can damage seals.

Also be aware of the recommended intervals for changing the coolant. Coolant quality has a significant effect on pump life.

Choose water pumps from trusted and leading manufacturers

Water pumps for today’s vehicles are technologically advanced products. Considering their critical role in the vehicle’s drive system, choose pumps from leading manufacturers with OEM experience.

Dayco is a global leader in the research, design, manufacture and distribution of essential engine drive systems and aftermarket services for automotive, truck, construction, agriculture and industrial applications.

Our mission is to deliver innovative products and services to the market that move the world forward, always.

Through our expertise in transferring power quietly and efficiently, Dayco has emerged as the leading global system solutions provider for hybrid electric vehicles. Dayco’s 100+ years of experience in drive systems allows us to equip all customer applications around the world with the most effective drive systems to meet customer specific performance requirements. Dayco’s world class global distribution network services the aftermarket industry with a full offering of kits and products to meet each local market’s need.

We accomplish this with a dedicated global team that respects one another, shows humility through continuous learning and acts like owners in everything we do. Discover all the codes of the water pump range by accessing the Dayco Catalog.