REMOVING AND INSTALLING/REPLACING WATER PUMP (N52K)
WARNING: Danger of scalding! Only perform this work after engine has cooled down.
Recycling:
Catch and dispose of drained coolant in a suitable container.
Observe country-specific waste-disposal regulations.
IMPORTANT: If a water pump that has already been operated is reused, it must be filled with coolant immediately after removal.
Mixture ratio, water : coolant = 1 : 1
Protect plug connections against coolant and contamination.
Cover plug connections with suitable materials.
IMPORTANT: Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
Unfasten hose clip (1).
For tightening torque refer to 11 53 5AZ.
Remove coolant hose.
Unfasten hose clip (2).
For tightening torque refer to 11 53 3AZ.
Remove coolant hose.
Disconnect plug connection (3).
Release screws (4).
For tightening torque refer to 11 51 1AZ.
Fig. 261: Plug Connection, Screws And Hoses
Installation:
Replace aluminium screws.
Remove electric water pump (x) via x.
Installation:
If the electric water pump is reused, it must be rotated one turn due to the breakaway torque at the blade wheels.
Assemble engine.
Venting instructions must be observed without fail.