Audi Water Pump Replacement Information

Audi Water Pump Plastic Impeller Controversy

Any automotive part has the potential for failure. This includes water pumps, no matter what type of impeller it's fitted with. Pictured are examples we've collected that show that even water pumps with metal impellers can fail (separate/spin on the shaft, internal bearings seized).

Why did Blauparts create this video?
What about metal water pump impellers?

Blauparts felt it was important to bring owners up-to-date regarding the advanced PPS composite material that is being used on most models from the factory. The implementation of PPS is just one example of the continual improvements being made in water pump design.

We believe it's important to use the OEM water pump design. If your car was designed with a PPS impeller, use a PPS replacement. If your car was designed with a metal impeller, use metal. Respecting the automobile engineers design is the wise course. Accordingly, our timing belt kits include the intended OEM design water pump.

Any automotive part has the potential for failure, including water pumps. Whether they're fitted with a metal or PPS impeller. Pictured to the right are some examples that even water pumps with metal impellers can fail (separate/spin on the shaft, internal bearings seized). Blauparts employs internal quality control disciplines with the intention of preventing problems for our customers before they're even detected. With this goal in mind, statistical quality and root cause analysis is key. In a recent quality query for the 2009-2010 sales year we found that the return rate of our water pumps was only 0.173%, of which 0% where returned due to PPS impeller failure! Looking all the way back to 2007 when we first started using water pumps with PPS impellers in our timing belt kits, we have never had a warranty due to a PPS impeller cracking or slipping on the shaft.

Advantages of of PPS: http://forums.tdiclub.com/showpost.php


When nearing a timing belt and Audi water pump replacement (60,000 - 90,000 miles), many owners carefully research different Audi timing belt kits and the individual components. If you've researched Audi water pumps at all, you may have noticed a controversy regarding metal impellers and plastic impellers?

Q) Many claim that 'plastic' Audi water pump impellers are junk. Why?

A) Earlier impellers were composed of a plastic called Durethan. In the high temperature environment of a coolant system, it encountered reliability issues. This plastic was not heat resistant enough at temperatures over 212° F (100° C). Since engine operating temperatures function in the 190-197° F range (87-92° C), this pushed Durethan to it's designed heat threshold. It increased the risk of the impeller cracking or slipping on the shaft. This is why so-called 'plastic' water pump impellers have developed a bad reputation.

Thankfully, European car manufacturers, including Audi, don't use Durethan water pump impellers anymore! Starting around 2000, a new advanced material called PPS was progressively integrated into Audi water pump impeller design and now nearly all new Audis and VWs come from the factory with PPS water pump impellers.

Q) What is PPS and why have they chosen to use it?

A) PPS is short for PolyPhenelineSulfide and is an advanced semi-crystalline polymer reinforced composite.

European car manufacturers' decision to implement PPS in their water pump design, this was a conscious, purposeful choice on their part. Where the Audi water pump was once a commodity product, it is now considered to be a crucial technical component of coolant and engine systems.

In the course of engine development, the engineer's primary target is to achieve the BEST engine performance and efficiency. In order to accomplish this, the Audi water pump needs to produce and maintain precise coolant circulation rates. These rates sustain optimal engine temperature, fuel economy, and emissions. Above all other tested products, engineer's found PPS to be the superior choice.

Audi water pump impeller - PPS features 1
Audi water pump impeller - PPS features 2

Q) What makes PPS so great?

A) PPS has a heat tolerance of up to and over 400 F; which is double the operating temperatures of the engine.

PPS has a high chemical resistance. This gives the water pump impeller a greater degree of strength over long-term exposure to high temperature and 'long-life' coolant.

PPS material is impervious to rust and resists corrosive breakdown.

The advanced composite of PPS provides an ideal water pump impeller weight. What this translates to is less wear and stress on internal bearings.

PPS allows for more elaborate impeller profiles. In other words, the geometry of the fins can be very complicated. Perfect flow rates can be more accurately achieved.

PPS is able to be manufactured smoother than other materials. This means less friction, less turbulence, and less cavitation while operating in the cooling system.

PPS Water Pump Impeller

Metal Water Pump Impeller

Audi water pump impeller - PPS closeup Metal Audi water pump impeller - Metal closeup
Example of a 2.8 liter 30 valve water pump shown.
PPS is able to be manufactured smoother than many materials. This means less friction, less turbulence, and less cavitation while operating in the cooling system. The geometry of the fins can be very complicated. Perfect flow rates can be more accurately achieved.
The correct flow rate (equivalent to the project) depends on the design and finish of the water pump impeller and volute. The volute and impeller must be machined at the same tolerances and parameters as the OE design in order to produce the engineers intended flow rate. Replacing it with one of differing material, weight, shape, or profile will negatively affect the intended performance and reliability of the car.
Audi water pump impeller - testing

Q) Did designers make this decision lightly?

A) Absolutely not! PPS was closely studied, monitored, and tested on water pumps taking into consideration many differing variables.

Consider a few of the following:

How hard an engine has to work is it's relative load. Stress and challenges placed on the engine contribute to heat generation. A water pump must handle the stresses of long steady drives thru the plains of Kansas as well as the rigors of climbing steep hills in the mountains of Colorado.

Engines with PPS water pumps were tested in varying ambient temperatures. Whether you're driving in 110° heat in downtown Phoenix or cruising along in -40° Canadian winters, the water pump must help maintain the correct engine temperature no matter what the extreme.

Due to various engine sizes and horsepower, heat displacement and buildup is a key factor in any coolant system. A water pump's ability to properly cool the engine is extremely important.

PPS water pump impellers were tested at all driving speeds. The RPM's were factored in as well. PPS would have to operate in perfect balance with the constantly changing airflow around the radiator. This is an important measurement since driving can range from the high speeds of the to slow, stop and go city driving.

Throughout all this rigorous testing, research, and development, PPS continued to produce efficient coolant flow rates and engine performance. PPS was selected to be the top choice for manufacturing water pump impellers. If your Audi or Vw model is specifically designed to use a PPS water pump impeller, replacing it with one of differing material, weight, shape, or profile will negatively affect the intended performance and reliability of your car.

You can be confident that using an advanced PPS composite impeller on your car, when part of the OEM design, is the ideal decision.

Car manufacturers like Ferrari, Lamborghini, BMW, Alfa Romeo, Fiat, and Maserati all pursue designing state-of-the-art engines using PPS pump impellers. These companies make some of the most exotic and expensive cars in the world! If a water pump fails in one of these cars, the results can be catastrophically expensive! Engineers certainly took this into consideration.

Their confidence in PPS impellers is reassuring. Now you know what the best engineering minds in the automotive industry know. We at Blauparts have consulted first-hand with water pump engineers and manufacturers on this very subject. Because of their expertise and our decades of Audi Vw experience, we trust PPS. Use the Audi water pump impeller designed for your model and respect your car!

 
BACK TO TOP

Audi water pump replacement kit - Audi timing belt kits -
Blauparts Audi Timing Belt Kit
Audi Timing Belt Kits
Audi Timing Belt Kits - 4 Cylinder Engines
Audi Timing Belt Kits - 5 Cylinder Engines
Audi Timing Belt Kits - 6 Cylinder Engines
Audi Timing Belt Kits - 8 Cylinder Engines
BLAU® Audi timing belt kits contain components from OEM manufacturers
that have achieved one or more of the following quality certifications:

High quality Audi water pump timing belt parts

Blauparts only supplies the highest quality water pumps that are manufactured using the OEM design and genuine components (i.e. internal bearings, seals, impeller). These pumps are individually tested using specific sealing porosity tests, involving resistance of the flange/pulley and impeller to axial movement. What does all this mean? Significantly greater reliability over other aftermarket pumps!

What else makes our Audi timing belt kits unique and different than the other guys? Blauparts timing belt kits come with decades of our specialized Audi repair service experience. The components in these timing belt kits are the very same ones that we use in our service repair facility on a daily basis. We use nothing but the BEST in OEM (original equipment manufacturer) quality parts. Blauparts is dedicated to choosing timing belt part manufactures that have been TUV / ISO 9001 / TS16949 quality certified. Every part put into these kits have been checked to ensure the perfect fit and highest quality. We're confident that after you receive our kit you'll agree that they are the most complete and highest quality ones on the market!

BLAU® Audi timing belt kits contain components from one or more of the following high OEM quality suppliers:
Audi timing belt parts 1Audi timing belt parts 2Audi timing belt parts 3
Error processing SSI file