V90 L6-2.9L VIN 96 B6304S (1998)
Timing Belt Tensioner: Description and Operation
The tensioner consists basically of a spring and hydraulic damper.
The plunger is displaced outwards when the belt tension is too low, forcing oil to flow from one side of the plunger to the other, through a non-return
valve, until the pressures on both sides are equalized and the tension is restored.
If the belt tension is too high, oil is forced to flow in the reverse direction through a leak-off channel, again equalizing the pressures and correcting the
tension.
