The benefits of car electric water pumps

Modifying and improving: "Electric water pumps"

The coolant needs to run round the engine taking the heat from the block and dissipating it in the radiator.

Most cars come with mechanical water pumps which have a number of drawbacks, will take a look at the benefits of upgrading to an electric water pump.

Mechanical pumps take a lot of power from the engine. They also rotate and therefore pump in proportion to the engine RPM. This does an adequate job but causes the following 2 issues.

  1. After a hard run with lots of heat in the engine the pump will slow down as you slow down. This can mean the engine temperature raises to dangerously high levels.
  2. Running straight from the crank it exerts a large pull on the engine and is engaged all the time. This effectively saps power.

This is tolerable on a standard car which rarely is driven hard. But when you have a highly tuned car and frequently take it for a spirited drive you can start to experience problems associated with overheating.

The solution then is to go with an electric water pump. This has a separate controller and allows much more control over the flow of coolant around the engine.

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  1. You can preset the engine temperature for high (better economy) or cooler (better performance).
  2. The average temperature is much closer to the preset temperature.
  3. The electric pump is only working when the engine is up to temperature allowing the engine to warm up more quickly.
  4. The pump can run after the car is stopped to cool any residual hot spots.
  5. Water speed can be faster than with a mechanical pump when required.
  6. As the pump is only running when required and at the speed required mechanical power losses from the engine are minimal.
  7. Electric water pumps weigh a lot less than their mechanical counterparts.

So there are many benefits from an electric water pump. When you fit this you remove the engine thermostat which controls the flow around the engine as the new EWP controller does this. For simple installation many owners remove the mechanical water pumps impeller to reduce drag but retain the belt tension and pulley.

What are the drawbacks? Reliability has been sited as a possible issue. Electric motors wear whereas the mechanical water pumps pretty much keep on going.

Although we should note that on certain VAG engine water pumps you have plastic impellers which break requiring complete replacement of the whole water pump. As long as you keep an eye the condition of your engine you should have little trouble with an electric water pump.

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