12 31 020 Removing and installing/replacing alternator (liquid-cooled) (M73)

Switch off ignition.

Disconnect battery negative leads from battery and lay to one side.

Remove complete left intake filter housing.

Remove radiator, refer to 17 11 000 REMOVING AND INSTALLING RADIATOR

Detach water hose (1) from water pump.

Release screw (2).

Fig 1: Detaching Water Pump Hose

Detach water hose (1) from outer jacket for alternator.

Fig 2: Detaching Alternator Outer Jacket Water Hose

Detach plug (1) from alternator.

Release nut (2).

Tightening torque, refer to ENGINE - TIGHTENING TORQUES .

Disconnect battery positive lead from alternator.

Fig 3: Detaching Plug From Alternator

Remove alternator drive belt, refer to V-RIBBED BELT WITH TENSIONER .

CAUTION: Remove screw (1) completely on completion only.
Release screws on alternator.
Remove screw (1) half-way.
Pull out alternator a little and allow coolant to drain of f.
Remove screw (1) completely.
Pull alternator completely out of outer jacket and removed towards top.

Fig 4: Removing Alternator From Outer Jacket

Installation:

Replace sealing ring (1).

Fig 5: Replacing Sealing Ring

Replace alternator pulley.

Unfasten nut with special tool 12 7 110, bracing alternator shaft with Allen key or multi-tooth socket wrench.

Tightening torque, refer to ENGINE - TIGHTENING TORQUES .

Fig 6: Assembling Special Tool And Replacing Alternator Pulley