Topping up/extracting fluid, checking oil level (M4 Convertible)

• The hydraulic fluid does not have to be changed because the system is filled with life-time oil filling.
• In the even of leaks, only the approved hydraulic fluid may be used: Aral Vitamol ZHM, BMW part number 54 34 0 394 395 (250 ml)
• All hydraulic cylinders must be completely retracted (soft top closed)

Necessary preliminary tasks: 

• Remove TRIM PANEL FOR LUGGAGE COMPARTMENT SIDE MEMBER on left and right.

Unfasten screw connection (1).

Tightening torque 51 71 11AZ .

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Feed out control unit (1).

Release cable strap (2).

Release retaining straps (2).

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Fold open sound insulation (1).

Checking oil level: 

Oil level must be within the marks (arrow in illustration) when the assembly is horizontal.

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Topping up oil: 

Lift out hydraulic unit (1) a little.

Undo oil filler plug (2).

Pour in required oil quantity.

Installation note: 

Check oil level in the meantime.

Pour in hydraulic fluid only up to marking on oil reservoir.

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Provide a suitable collecting vessel.

Extracting oil: 

Lift out hydraulic unit (1) a little.

Undo oil filler plug (2).

Tilt hydraulic unit (1) and let oil flow out or draw off with suitable auxiliary equipment.

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