When your engine is running it can get very hot. To prevent the engine overheating, the water pump does what its name suggests. Pumping water around the engine and then carrying the hot water to the radiator where it is cooled and then pumped back through the engine. 

This makes sure everything runs at the correct temperature and keeps the engine performing at its best. 

If the water pump fails then the engine will overheat and break down. Seeing as that’s a very expensive endeavour, it’s best to keep the water pump working properly. 

What is a water pump?

A water pump is either run off of a belt attached to the engine or run off the battery. The engine powered one is mechanical and the battery powered one is electric.

Both have a small impeller inside a casing, usually made from iron or alloys. This impeller draws water from the radiator via the inlet and sends water through the engine through the outlet. They spin a very high speed to create the required suction and move the required volume of water through the engine.

Why do you need a water pump? 

To prevent your engine overheating and blowing a head gasket, your water pump has to be fully functional. If coolant is properly circulated through the engine then the resulting damage from overheating can cost far more than just a new pump.

What symptoms mean you need a water pump replacement? 

A good indicator is coolant leaking onto the ground, your temp gauge climbs at low speeds. Sometimes you’ll notice a whining or rattling noise from the engine bay when the engine is running. In newer models, the electric fans will stay on longer after the car is turned off

How to replace a water pump

• Firstly the car is hoisted off of the ground and the radiator is drained via the drain plug
• All connecting belts and objects in the way of the pump are disconnected and removed
• The water pump is unbolted from the engine block and removed
• The thermostat will be checked to see if it needs replacing as well
• The new water pump is bolted to the engine with a new gasket
• The connecting belts and other objects are reconnected to the engine
• The radiator is refilled with coolant and the engine is started to run the coolant through
• The air is bled out of the system and the car is test driven up to operating temperature and checked for leaks

How much does a BMW water pump replacement cost?

Typically in the range of $350 to over $850 depending on the difficulty and cost of the new pump.

How often do I need a new water pump for my BMW? 

It varies based on the make and model but they are generally only replaced when an issue arises that requires replacement. 

Is a broken water pump unsafe? 

It can cause catastrophic damage to the engine, so although not dangerous to your health it can seriously damage the most expensive thing in your car - the engine. 

If a problem arises that requires the water pump to be replaced then you should do so as soon as possible.

You can find a Water Pump Replacement mechanic near me with My Auto Shop