Diesel engines
Replacing the auxiliary drive belt
In this manual: Diesel engines
8steps
~48min
2/5difficulty
Done 0 of 8
REMOVAL
- Remove:
- the front right wheel,
- the engine undertray.
- Using a wrench, turn the bolt (1) of the automatic tensioner clockwise (arrow) to release the belt tension (2) (Fig.16).
- Remove the auxiliary drive belt (2).
INSTALLATION Installation is the reverse of removal, observing the following points:
- check that the tensioner and idler pulleys rotate freely (no play, no excessive noise, no hard spots),
- fit the belt following its routing (Fig.17).

Fig. 17
Auxiliary drive belt
- Without air conditioning
- With air conditioning.
- Crankshaft pulley
- Water pump pulley
- Idler pulleys
- Alternator pulley
- Tensioner pulley
- Air conditioning compressor pulley.

Fig. 16
Make sure the belt is correctly seated in the grooves of the various pulleys.Test yourself
A quick Mercedes-Benz B-Class quiz: every answer comes with an explanation and a link to the manual page.
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