64 52 521 Replacing A/C Compressor

64 52 521 - Replacing A/C system compressor (N52K)





Special tools required:





Warning!
Risk of injury!

Refrigerant circuit is under high pressure!

Work on the cooling system may only be carried out when it has cooled down.

Follow safety instructions for handling R134a refrigerant.

Follow safety instructions for handling refrigerant oil.

Avoid contact with refrigerant and refrigerant oil.





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.

The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.

Jointing torque and angle of rotation must be observed without fail (risk of damage)!





Important!
Risk of damage!

Restart engine only when A/C system has been correctly filled.

Read and comply with notes on replacing compressor. Service and Repair

Follow instructions 64 52 ... Instructions For Compressor Replacement for opening and replacing parts in refrigerant circuit!

If A/C system is opened for more than 24 hours:

Replace desiccant insert for A/C system





Necessary preliminary tasks:
- Drawing off, evacuating and filling the A/C system 64 53 515 Replacing Desiccant Insert For Air Conditioning System are not included in the time value given for this work operation
- Release expansion tank and place to one side
- Remove alternator drive belt 64 50 009 Drawing Off, Evacuating and Filling A/C System (R 134a)
- Remove coolant thermostat Service and Repair





Release screws (1) and disconnect plug connection on compressor.

Disconnect pressure and suction lines.

Installation Note:
Replace all sealing rings and moisten with refrigerant oil.

Tightening torque 64 52 1AZ Service and Repair.





Important!
Seal openings or lines on compressor with special tool 32 1 270 to prevent escape of media and fouling.





Note:
Secure compressor (3) against falling out.

Release screw (1).

Release screws (2).

Tightening torque 64 52 3AZ Specifications.

Remove compressor towards front.





After installation:

- Evacuate and fill A/C system
- Fill cooling system Specifications, vent and check for leaks.
- Assemble engine