11 51 000 Removing and installing/replacing coolant pump (N55)
Only perform this work after engine has cooled down.
Mixture ratio, water: coolant = 1: 1
Protect plug connections against coolant and contamination.
Recycling
Catch and dispose of drained coolant in a suitable container.
Observe country-specific waste disposal regulations.
Installation note:
- All screws, nuts, bolts and hose clamps removed during the repair must be replaced.
- Retaining elements on chassis and suspension and steering parts must be replaced.
Necessary preliminary tasks
- Follow diagnosis instructions.
- Remove engine splash guard . See 51 47 490 REMOVING AND INSTALLING/REPLACING FRONT UNDERBODY PROTECTION or 51 47 490 REMOVING AND INSTALLING/REPLACING FRONT UNDERBODY PROTECTION (AWD) .
- Drain coolant. See 17 00 005 DRAINING AND ADDING COOLANT (N55) .
- Remove THERMOSTAT .
- Remove REINFORCEMENT PLATE (only E70, E71, E84).
Disconnect plug connection (1).
Release coolant hose (2).
Installation note:
Note installation hose clamps.
Tightening torque: 11 53 9AZ .
Release coolant hose (1).
Installation note:
Note installation hose clamps.
Tightening torque: 11 53 5AZ .
Follow assembly instructions
Installation note:
Hose clamps (1) must be installed in the center of the marked area (see Fig 3).
Release screws (1).
Tightening torque: 11 51 2AZ .
Installation note:
Replace aluminum screws.
Unclip cable (1) from bracket.
Release screw (2).
Tightening torque: 11 51 2AZ .
Installation note:
If the electric coolant pump is reused, it must be rotated one turn due to the breakaway torque at the impellers.
Assemble engine.
bleeding instructions must be observed without fail . See 17 00 039 VENTING COOLING SYSTEM AND CHECKING FOR WATERTIGHTNESS (N55) .