This article will discuss how to set the proper timing belt tension on an Audi VW 4.2L V8 engine. Several popular questions are asked by our customers regarding this procedure. Questions like, the instructions for installing this timing belt kit leave the timing belt tension so tight that it appears to bind the water pump and hydraulic damper. Will this create a potential failure of these parts? Should the tension be loosened a bit? Does having a tight 4.2L V8 timing belt tension affect the longevity of the timing belt tensioners? Does tight 4.2L V8 timing belt tension affect the longevity of the water pumps? Does your kit contain aftermarket belts? This article will answer these questions, and apply to the following models and timing belt kit part numbers listed below.
Vehicle Applications:
- Audi A6 Timing Belt Kit - 2001-04 w/ 4.2L 8 Cylinder Engine Code AWN
- Audi A8 Timing Belt Kit - 2001-03 w/ 4.2L 8 Cylinder Engine Code AKB or AUX
- Audi A8 Timing Belt Kit - 2004-06 w/ 4.2L 8 Cylinder Engine Code BFM or BGK
- Audi S8 Timing Belt Kit - 2001-03 w/ 4.2L 8 Cylinder Engine
- Audi S6 Timing Belt Kit - 2002-03 w/ 4.2L 8 Cylinder Engine Code BBD
- Audi RS6 Timing Belt Kit 2003-04 w/ 4.2L 8 Cylinder Turbocharged Engine Code BCY
- VW Phaeton Timing Belt Kit - 2004-06 w/ 8 Cylinder 4.2L Engine
- VW Touareg Timing Belt Kit - 2004-07 w/ 8 Cylinder 4.2L Engine
Timing Belt Kit Part Numbers:
- GH21617-2
- GH21118
- GH21118-1
- GH21132
- GH21132-1
Question 1) The instructions for installing this timing belt kit leave the timing belt tension so tight that it appears to bind the water pump and hydraulic damper. Will this create a potential failure of these parts? Should the tension be loosened a bit?
Insert a 5mm drill bit between the hydraulic damper piston and the tensioner pulley casting arm. Allow the tensioner pulley casting arm to rest on the 5mm drill bit.
Using eccentric tool T40009 rotate the eccentric tensioner pulley counterclockwise until the arm of tool T40009 is aligned with the center of the water pump pulley and torque to 16 ft-lbs. When doing this step make sure the 5mm drill bit is still properly in place as outlined in the previous step.
Remove the 5mm drill bit from between the hydraulic damper piston and the tensioner pulley casting arm.
Compress hydraulic damper, remove damper holding pin, and allow the damper to un-compress. You will want to allow the hydraulic damper to un-compress thoroughly for the best belt tension.
Note 1) After removing the damper holding pin, a 5-7mm distance between the top of the hydraulic damper body and the tensioner pulley casting arm should be maintained.
Note 2) The belt tension will be tight. After the crankshaft lock pin (Step 32) has been removed and the camshaft pulleys torqued to spec, rotating the engine two full revolutions by hand. This will allow the new timing belt to center, align, and properly relieve any binding of the belt that might exist. As described in our Audi VW 4.2L timing belt instructions, the distance between the top of the hydraulic tensioner damper body and the cast tensioner lever arm should be 5-7mm after rotating the engine by hand for two full revolutions.
Question 2) Does having tight 4.2L V8 timing belt tension affect the longevity of the timing belt tensioners and idlers?
Answer: If you use INA OEM specification timing belt components and you follow the steps outlined above the answer is NO. These components are engineered and designed to perform under load. All BLAU 4.2L V8 Timing belt kits contain INA OEM timing belt tensioners and belts. These are the same OEM tensioners as those directly supplied to the O.E. automotive manufacturer. That means they are designed and engineered for the same specifications and life span as O.E. and will last as long as the genuine components you buy from the dealer.
Question 3) Does tight 4.2L V8 timing belt tension affect the longevity of the water pumps you use?
Answer: The Graf OEM water pumps used in our kits have been engineered with a large enough displacement-sized OEM bearing to carry the heavy load that the timing belt is applying to it. With proper timing belt tension, procedures followed by the water pumps are designed to exceed the specified service intervals.
Question 4) Does your kit contain aftermarket belts?
Answer: The INA Gates 4.2L V8 timing belt in these kits should NOT be considered 'aftermarket'. INA Gates is an OEM supplier to many automotive manufacturers for a variety of models.
We would like to encourage installers to read the entire instructions ahead of time and then to take the time to correctly follow the instructions for a failure-free installation. If you have unanswered questions during the repair process, feel free to contact us.
