Water pump, a key element in engine cooling, is one of those components that, if it breaks down, can cause our vehicle stop running. Its function is to transfer excess heat to the outside to prevent the engine from overheating in addition to ensuring optimal sealing, preventing antifreeze or coolant leaks that can cause this overheating. There are several reasons why a water pump can fail such as improper use of sealants, corrosion damage, contamination… but there is also the possibility of the water pump failing due to common mistakes when installing it.

In today’s article we talk about the top 5 mistakes in the installation of a water pump and how to effectively install this key element of the cooling system.


Installing a water pump: Mistakes


1. Cooling System Preparation


One of the main and often overlooked problems is in the preparation of the system through which the water pump will circulate the coolant.

Before installing a water pump it will be especially important to flush, drain and refill the cooling system with the OE (original equipment) specified coolant mix. On the contrary, the correct operation of the new water pump would be jeopardized.

Dolz Tip: When preparing the cooling system, if you notice that the old coolant is very dirty, it is advisable to check the thermostat and replace it if necessary.


2. Improper mix of coolant and water


Another common error is found in contamination caused by the incorrect mix of coolant and water or its improper use. Contaminated or improperly mixed coolant can cause corrosion problems, the dreaded cavitation, and cause leaks between the two contact faces of the water pump’s dynamic seal.

When choosing the right coolant, it is essential to check the expiration date and follow the vehicle manufacturer’s recommendations, as each individual engine is made from different materials and has specific needs.



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3. Incorrect use of sealing paste


The use of sealing paste in the water pump is only necessary in those that are supplied without a gasket. Otherwise, if we add sealant when it is not needed, we will cause any particle of sealing paste that circulates through the cooling circuit coming from the pump gasket, which may affect the functionality of the dynamic seal, preventing the correct sealing function and causing a failure premature of it.

Incorrect use of sealing paste will directly affect the life expectancy of the water pump. Therefore, unless specified or referenced without a gasket, avoid the use of sealants.


4. Water pump dry rotation


Another mistake to avoid during installation is dry rotation of the water pump.

When refilling the cooling circuit after replacing the water pump, many manufacturers recommend that the pump be turned by hand until it is full. This fine-tuning of the pump can reduce the possibility of loss of the “mechanical” seal since the coolant liquid reaches the component of the mechanical seal creating a film that will prevent its spillage.

Otherwise, if the pump runs dry, it will cause damage to the seal, which may lead to premature leaks or squeaking noise in the water pump.


5. Water pump and timing belt


One of the most common mistakes is to overlook the distribution when we are doing the installation of the new water pump. The water pump is driven by the belt transmission system, which means that combining the replacement of both systems improves the quality and the safety of the process, which is why it is a highly recommended practice.

Previously the replacement of these two components was carried out separately, but nowadays it is more and more common to carry out this operation at the same time. This allows better vehicle performance and longer average lifespan of the water pump.

If the timing belt and other related items are installed incorrectly, this will directly affect the performance of the water pump.



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Discover Dolz’s water pump range


We manufacture more than 5.5 million units per year over a range which comprises:

  • Water pumps for passenger cars
  • Water pumps for industrial vehicles
  • Auxiliary electric water pumps
  • Variable water pumps
  • Electric water pumps

All our range has the ISO 9001:20015 certification, which means quality 100% tested. A process as simple as it is fundamental and for which, among many other factors, DOLZ water pumps are the pumps with the highest quality on the market.


Main characteristics of the range


  • The DOLZ range is made of 1300 references, among which 990 for cars applications & 18% only for Asian applications,
  • 95% coverage of the European car parc.
  • 95% of the DOLZ range includes a Silicon Carbide Dynamic Seal, that guarantees optimum tightness and durability of the water pump,
  • Water pumps designed according to OE specifications,
  • Automatized manufacturing process that guarantees an excellent quality.

All of them have 100% cast aluminum material, resistant to wear and OE equivalent, always following the highest standards.

Dolz, an expert manufacturer of water pumps since 1934.

Get in touch to learn more about our range of water pumps and other Dolz product lines.

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