You might think a water pump doesn’t sound very exciting or important, and a bit of water dripping underneath your car isn’t too big a deal. Well, a broken or damaged water pump can easily lead to severe engine damage, including a chance of it seizing completely.

We don’t have to tell anyone just how expensive repairing engine damage is. In many cases, it’s way more than the car’s worth. So, just what is a water pump (in a car, of course)?

What does a car water pump do?

Your water pump creates a steady flow of coolant around your vehicle’s cooling system. It establishes the proper circulation to keep all the parts working under their optimum temperatures and that all the excess heat is dispensed safely into the environment.

The coolant flows through the engine block, picking up the excess heat, and then through cooling galleries to dispel it. Without the pump the coolant couldn’t flow around these critical components, would evaporate, the engine would overheat, and possibly seize.

The timing belt drives the water pump—often called the Serpentine belt—and their relationship is vital to the survival of your engine. We’ll look deeper into this a little later in the article.

What does a car water pump replacement cost?

The price of water pump replacements can vary considerably from car to car. The job could cost as little as £200 or well over £500. The average price in the UK is around £350, but if you choose Fixter to find you a great deal in your area, you could end up paying quite a lot less.

How can you tell if there’s something wrong with your water pump?

  • The first things to look for are puddles or pools of coolant under your car—especially around the engine.
  • If you lift the bonnet and you see fluid around the engine bay where the water pump sits, that’s a sign there could be a leak or a seized pump.
  • The car won’t start (it could be too late, by this point).
  • Your engine temperature is higher than normal or overheating.
  • The engine temperature warning light has illuminated on the dashboard.
  • There’s steam coming from your engine.
  • You can hear whining, knocking, buzzing or squealing sounds.

How long does a car water pump last?

This is a tricky area to pinpoint, as there are plenty of cars on the roads, still running as well as they ever did on a water pump with over 200k miles of service. That said, there are probably just as many that failed covering distances of only 50k or 60k miles.

Manufacturers suggest that their pumps should be able to provide around 100k of service, so depending on your vehicle usage, you should consider a replacement anywhere between 50k and 100k miles.

Another schedule, suitable to most drivers, is to replace it—along with your timing belt—around every 5 years.

If you still have your owner’s manual, it’s always a good idea to see what the manufacturer recommendations are. Every car operates under slightly different pressures and conditions, varying the lifespan of their components. Only your manufacturer will understand the precise, expected lifespan of each of those that operate inside their vehicles.

The relationship between your water pump and the timing belt

Because the function of the water pump relies heavily on the condition of your timing belt, it’s standard to replace both at the same time.

Another reason for carrying out the work together is that there’s a lot