Timing belt tensioner: common defects and their signs

1. Corrosion and wear-out of elements of timing belt tensioning mechanism.
   • Knocking and screeching from under the timing mechanism cover.
   • Jerks during engine start.
   • Loss of engine power.
   • Slipping or tearing of the toothed belt.
2. Mechanical and thermal damages of components.
   • Leakage of tensioning roller lubricant.
   • Excessive vibration (for cars with the diesel engine).
   • Accelerated wear, damaging of the timing belt.
   • Unstable operation of the engine.

How to replace the belt tensioning mechanism?

It is recommended to check the timing belt tensioner during every scheduled maintenance of the vehicle. At the average, replacement of the tensioning mechanism should be performed every 70 000 operational kilometers. This recommendation also concerns the tensioner lever of the V-ribbed belt.

The broken toothed belt tensioner can not be restored. At appearance of the defects noted above, the component should be replaced along with the tension roller and the timing belt.

Replacement of the tensioner lever of the timing belt requires special tools and skills, so it should be entrusted to car service professionals.