CAT Inside Line – Mercedes-Benz C-Class (- 2014)
Gates says that an increase in vibration and, consequently, greater noise levels from the drive system in some 1.8 (Petrol) and 2.0 (Diesel) engines in this range, are often attributed to the drive belt – in error.
In such cases, replacing the belt alone will not solve the problem, as noise levels will continue and wear to other components within the drive system will increase after the belt has been replaced. Gates advises that the Overrunning Alternator Pulley (OAP) should be inspected.
OAPs provide a vibration dampening function and are designed to accommodate speed fluctuations in the Auxiliary Belt Drive System (ABDS). This reduces stress, strain and therefore wear and tear on the belt. This helps to prolong the life of the belt and other associated components within the ABDS.
A failed OAP is less efficient and the level of vibration – and noise, increases. The belt is blamed and often changed without resolving the issue.
Unchecked, the failed OAP provides no damping. Premature drive system failure becomes likely.
OAPs should be inspected, with a view to replacement.
A drive system overhaul of this nature will not only resolve the noise and vibration problem, but will help to prolong the operational lifetime of the drive system as a whole.