What is a water pump, how does it work and why is it important?
The water pump ensures that enough coolant is flowing around the cooling system and engine in order to remove sufficient heat to prevent the engine from overheating. As the engine works harder (under higher loads), the water pump increases circulation in order to deal with the greater levels of heat produced.
Inside the water pump
Inside the pump is:
- An impeller (which might be made of either metal or plastic) with blades that push the coolant through the pump and out around the engine.
- The impeller is then mounted on a shaft with a seal assembly supporting it and allowing it to work without being impeded in any way.
How a water pump works
The water pump circulates coolant using centrifugal force. A belt connects the pump to the crankshaft, keeping it spinning. Some water pumps are driven by an electric motor instead of the engine. The coolant is pumped through the engine to absorb heat, then sent to the radiator to cool down before recirculating.
Importance of a water pump
If the engine overheats due to insufficient cooling, it can suffer major damage, leading to costly repairs. The water pump is crucial in preventing this by maintaining efficient coolant circulation.
Why do water pumps fail?
There will always be some water pumps that malfunction unexpectedly for a variety of reasons and therefore have to be fixed or replaced completely.
One main issue that can be encountered, and which K-Seal is capable of fixing, is the casing developing a leak. This allows coolant to escape which means it doesn’t circulate through the engine risking overheating issues.
The reasons why a water pump seal might begin to leak include:
- High temperatures – It is inevitable that at some point the polished rubber surface of the seal will succumb to the high temperatures it is subjected to every time the vehicle’s ignition is switched on. Tiny cracks or holes will subsequently develop and cause the water pump to leak coolant.
- Abrasive particles – It is possible for tiny abrasive particles to get into the pump and damage the seal, such as in tap water that has been mixed with antifreeze to create the coolant (this is why you should only use soft, distilled water if mixing coolant yourself).
- Electrolysis – Corrosive inhibitors in the seal plating deteriorate in effectiveness over time and the coolant becomes more abrasive the more it is used. As the inhibitors deteriorate and the coolant’s abrasiveness increases, electrolysis on the seal face occurs and coolant is allowed to leak through it. This is why regular flush-and-fills are recommended.
What are the symptoms of water pump failure?
There are several symptoms to look out for when identifying a water pump failure:
- Overheating – The engine may be overheating, which you may not be able to ascertain until the warning light comes on.
- Coolant leaking – Coolant may be leaking around the water pump through the weep holes on the casing. There will be a puddle on the floor when the car has stood in the same position for a few hours – follow the leak to its source. Coolant can be green, orange, or red.
- Whining noises – The water pump may be making more noise than it usually does when the engine is running. The source of the louder noise will probably come from a defective impeller or an impeller that is coming away from its shaft, in which case it will have to be replaced.
- Smoke – If you see smoke coming from your car’s engine, it could be a sign of a failing water pump. The water pump circulates coolant through the engine, and when it malfunctions, the coolant can overheat, leading to engine smoke.
Identifying a water pump failure early is crucial to avoid the cost of a full replacement. Spotting the issue sooner gives you the chance to use K-Seal to fix a leaking pump before going to a garage.
How to repair a water pump
Repairing a water pump typically involves replacing the faulty pump rather than repairing individual components, as water pumps are generally sealed units.
How much will water pump repair cost at a garage?
The cost of replacing a water pump will vary considerably depending on a number of factors, such as the garage you visit and the car you drive. The water pump replacement cost usually ranges between £120 and £375. It’s important to get quotes from a range of local mechanics so you can be sure you’re getting the best deal.
To avoid this costly replacement, you could first look at whether K-Seal can help repair your water pump and stop it from leaking coolant.
Can K-Seal fix my water pump?
If you want to avoid expensive mechanic bills but don’t have the technical knowledge or experience needed to resolve a leaking water pump in any other way, K-Seal is the option for you – it can fix most leaks in the water pump casing and in the hard seals (not suitable for hoses or soft seals).
Want to get hold of a bottle to fix your water pump? Use our simple stockist search facility and get back on the road – fast.
Could other parts of my engine be affected?
Although your water pump could be the source of your engine troubles, it might not be the only component you need to take a look at. Select an engine part in the interactive diagram below to explore your engine and the important components that keep everything ticking over.
Still not sure what the problem is? Try our 60 second problem solver to quickly identify what the issue is based on your symptoms.