Water Pumps
Fits MERCEDES-BENZ VIANO (W639) CDI 2.2 (639.711, 639.713, 639.811, 639.813, 639.815)
(2003)

What is a water pump?

A water pump, also known as a coolant pump is a device on your engine that forces the circulation of water (coolant) around your engine. The engines internal combustion process generates a lot of heat and as such the engine needs to be cooled down so as to prevent damage from overheating. A fully functioning water pump is essential to the general running of the engine.

There are 2 main types of water pump. These are:

• Mechanical water pump

• Electric water pump

What comes with a water pump?

Water pumps are sold with different parts depending on the original design and what the aftermarket makers decide to include. We would always recommend that you check the image of the part and the parts notes to see what is included.

These can be items such as:

• Water pump gasket

• Sensors or switches

• Flanges or pump backing plates or enclosures

How do I choose the correct water pump?

Comparing replacement parts against the original part number is one of the best ways to find the correct water pump. If you see more than one pump listed by the same brand there is likely compatibility notes that you need to observe. These can be factors such as:

• Engine code

• Manual or automatic transmission

• Vehicle manufacture date (this is not the date the vehicle was registered but the date it was made

• Engine number sequence (up to or after as specific number/letter

• VIN (chassis number) sequence (up to or after as specific number/letter

Sometimes there is a switchable or non-switchable water pump that matches the same OE part number. In these situations both the switchable and non-switchable water pump will be compatible with your vehicle. The mounting for the switch/sensor will likely be blanked off however the switch / sensor should still be fitted in the same position. This is general advice and we would refer you to the technical documentation of the part in all instances.

What brand of water pump should I choose?

All aftermarket brands are designed to meet or exceed the original specification however there are different price points and warranty offerings which may make the choice tricky.. Quite often the brand that has a longer warranty period would be regarded as a higher quality part. You can either choose a brand you are happy with or choose a brand within your budget with the longest warranty period available.

How can I tell my water pump needs replacing?

Replacing a water pump as soon as it is found to be faulty is very important. If the water pump suffers a complete failure while driving it would more than likely put a stop to your journey. Were you to continue there could be irreparable damaged caused to your engine.

Here are some symptoms of a faulty water pump:

• Overheating engine

• Steam escaping from under the bonnet

• Leaking coolant

• Loud whining noise from the engine