17 11... Clean the radiator ribs

Necessary preliminary tasks: 

• Remove fan cowl. See REMOVING FAN COWL WITH ELECTRIC FAN (N55) , REMOVING FAN COWL WITH ELECTRIC FAN (N63) , -or- REMOVING FAN COWL WITH ELECTRIC FAN (N63O1) .

Release screws (1) on left and right from cover (3).

Tightening torque: 5 Nm

Release screws (2) behind sealing lip.

Tightening torque: 5 Nm

Lift out cover (3).

Fig 1: Identifying Cover And Screws

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Check radiator (1) for dirt contamination.

Fig 2: Identifying Radiator

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To clean the radiator use a standard narrow vacuum-cleaner attachment (1) with a length of approx. 600 mm.

Fig 3: Identifying Vacuum-Cleaner Attachment

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Ensure that the cooler fins are not damaged.

Vacuum dirt off the radiator using a vacuum cleaner with a narrow attachment (1).

Fig 4: Cleaning Radiator Ribs Using Vacuum Cleaner With Narrow Attachment

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Only if transmission oil cooler or power steering cooler fitted: 

Lift up transmission oil cooler/power steering cooler (1) slightly.

Vacuum dirt off the radiator using a vacuum cleaner with a narrow attachment (2).

Fig 5: Lifting Up Transmission Oil Cooler/Power Steering Cooler And Vacuuming Radiator With Narrow Attachment

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N63 B40/44 O 0/1 only: 

Only partially detach radiator cover (1) at top.

Using a vacuum cleaner with a narrow attachment (2), vacuum off the dirt between the air conditioning condenser and the radiator.

Fig 6: Vacuuming Off Dirt Between A/C Condenser And Radiator -- N63 Engines

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Reassemble the vehicle.