Water Pump: Service and Repair

11 51 000 - Removing and installing/replacing water pump (N51)





Warning!
Danger of scalding!
Only perform these tasks on an engine that has cooled down.





Recycling:
Catch and dispose of drained coolant.
Observe country-specific waste-disposal regulations.





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.
Aluminium screws/bolts are permitted with and without
colour coding (blue).
For reliable identification:
Aluminium screws/bolts are not magnetic.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
If a water pump which has already been operated is reused, it must be filled immediately after being removed with coolant (mixture ratio 1:1 / water: coolant).





Necessary preliminary tasks:
- Remove coolant thermostat Service and Repair.





Disconnect water hose (1).
Disconnect plug connection (4).
Release screws (5).

Installation Note:
Replace aluminium screws.

Tightening torque: 11 51 1AZ Specifications.

Installation Note:
If the water pump is to be reused, it must be mechanically rotated once (breakaway torque at impellers).
One water pump rotation will be sufficient.





Assemble engine.
Venting instructions 17 00 039 Venting Cooling System and Checking For Water Leaks must be observed without fail.