Impeller pumps: Everything you need to know to replace or repair a water pump!

In this blog post you will read and learn everything you need to know about impeller pumps!

When it comes to maintaining a boat with an inboard engine, knowledge about the impeller pump is essential. This pump plays a crucial role in the engine's cooling system, and understanding how it works and how to handle it can prevent many problems. In this blog post we will discuss everything you need to know about impeller pumps, including tips and tricks for replacing and repairing impeller pumps.

What is an impeller pump?

An impeller pump is a type of water pump used in boats with an inboard engine. It works by using a rotating element called the impeller, which sucks in water and pumps it through the engine's cooling system. This ensures that the engine remains at the correct operating temperature and prevents overheating.

Why is maintenance important?

Like any other part of an inboard engine, the impeller pump requires regular maintenance. This is because the impeller itself wears out over time and can break, which can lead to serious damage to the engine if it is not replaced in time, and the impeller pump itself also wears out. Some wearing parts of an impeller pump are:

• The impeller
• The impeller pump cover
• The wear plate at the back of the impeller pump
• The water and any oil seal.
• The shaft of the impeller pump

Regular checks and replacements according to recommended maintenance schedules are therefore essential to ensure that your impeller pump remains in trusted condition.

How do you replace an impeller pump?

Replacing an impeller pump is generally not a difficult task, but it does require some knowledge and skill. Start by turning off the open water tap, then drain the open water system to prevent water from flowing into the boat. First disconnect both cooling water hoses, which supply and drain the outside water. Then remove the bolts that hold the impeller pump in place in the engine. These are often 4 M8 bolts (key or socket 13mm). After this you can pull the impeller pump out of the engine block. Please note that on some engines the gear wheel is held in the distribution by the impeller pump.

Repair of impeller pumps

Sometimes an impeller pump can be repaired instead of completely replaced. This may include replacing or repairing worn parts, such as damaged housings, leaking seals or broken bearings. However, it is important to know when repair is possible and when replacement is necessary for the safety and reliability of the motor and impeller pump. Not sure whether your impeller pump can be repaired or needs to be replaced? Contact us and we will be happy to help you!

Popular brands

There are various brands of impeller pumps, originally supplied by the engine manufacturer or aftermarket impeller pumps , these are often of higher quality because they have been further developed and have solved the errors of the original pumps. With us you will find a wide range of impeller pumps that can replace the original impeller pump of your marine engine. We also sell overhaul sets with which you can overhaul our aftermarket pumps if you have been using them for a number of years.

Below you will find a list of brand-specific impeller pumps that you can order from us:

• Impeller pumps for Volvo Penta engines
• Impeller pumps for Yanmar engines

In short, impeller pumps are essential to a properly functioning inboard engine, and it is important to know how to maintain, replace and repair them. With the right knowledge and care, your engine can continue to run smoothly and you can enjoy carefree boat trips on the water.

Also check out our blog about diagnosing a broken starter motor!

• Starter motor defective and how do I replace it? Step-by-step guide for Vetus, Volvo Penta, and Yanmar engines.