Removal and installation the air conditioning compressor (BMW 5 Series E28)

Since working on the system is potentially dangerous, we strongly recommend that all work on the air conditioning system be performed by a BMW dealer or air conditioning specialist. At the very least, do not remove any components of the system (hoses, compressor, nipple connections, etc.) until the system is completely discharged by a qualified technician. Read the precautions at the beginning of Section Air Conditioner Maintenance and Precautions.

When installing a new compressor, the battery/dehydrator should also be replaced (see section Removal and installation the air conditioning battery/dehydrator).

Removal

1. Discharge the air conditioning system (see warning above).

2. Disconnect the negative battery cable.

If your vehicle's radio is equipped with an anti-theft system, make sure you enter the correct code before disconnecting the battery.

If the instrument cluster displays the wrong language after connecting the battery, refer to Section Anti-theft audio system and instrument cluster language, which describes the procedure for installing the required language.

3. Disconnect the compressor clutch wiring.

4. Remove the drive belt (see chapter Routine car maintenance).

5. Disconnect the refrigeration lines from the rear of the compressor. Cap any open lines to prevent moisture and dirt from entering.



6. Working under the vehicle, unbolt the compressor from the mounting brackets, lift it and remove it from the vehicle.

Installation

1. When installing a new compressor, follow the instructions included with it regarding draining excess oil before installation.

2. The old coupling can be used on the new compressor.

3. Install in the reverse order of removal. All sealing rings should be replaced with new ones, specially made for use in air conditioning systems. Lubricate them with special oil before installation.

4. Have the system drained, recharged and leak tested by the same qualified person who discharged it.