[Vwdiesel] Timing belt life

[Sandy Cameron]

This snipped from the contitech web site

http://www.contitech.de/ct/contitech/allgemein/innovation/zahnriemen_e.html

High-tech timing belts keep running for the life of the engine 

 Technically, it isn't a problem. If the belt drive system and timing belt
are finely tuned to each other, the belts will last the lifetime of the car.

Examples from the VW corporation demonstrate that timing belts can indeed
last so long in actual use: on the 1.0 to 1.6 l gasoline engines on the
Lupo, Polo, Golf and comparable models of the Skoda and Seat brands, the
maintenance schedule no longer specifies an interval for belt replacement -
a lifetime of use for the benefit and safety of the drivers.

For the 2.0 l FSI engine, Audi does still recommend that the timing belt be
replaced after 180,000 kilometers, but the next handbook will supposedly not
include this recommendation. For most engines of the French PSA group, there
is practically no longer any change interval since the belts last about
240,000 kilometers or 10 years on a 1.4 l HDI 70 HP engine running in the
Peugeot types 307, 206, C3 and in the Ford Fiesta.

For the belt to function properly, it is crucial that all of the system
components - the belt and the automatic tension and idler pulleys - are
finely tuned to each other. 

The requirements placed upon timing belts are becoming ever more demanding.
But modern materials make the belts more reliable: where a timing belt might
have managed to last 10 hours on ContiTech's high-performance test benches
several years ago, it can now reach 500 hours thanks to high-quality tension
members in the timing belt. Glass cord tension members manufactured by just
a few specialized companies in the world and a special HNBR rubber compound
make operating temperatures between - 40 and + 150 °C possible and provide a
long service life. Test vehicles equipped with the CONTI HSN-POWER®, a third
generation timing belt, have easily reached 300,000 kilometers without a
belt change.

The pump-injector engine supplied by VW for various vehicles demonstrates
just how strong timing belts of modern materials are. The original chain
drive kept causing problems, so VW decided to only use special timing belts
from ContiTech.