64 52 521 Replacing A/C system compressor (N52, N52K, N53)
Refrigerant circuit is under high pressure!
Follow safety instructions for handling R 134a refrigerant See 6450... SAFETY INSTRUCTIONS FOR HANDLING R134A REFRIGERANT or 6450... INSTRUCTIONS FOR HANDLING REFRIGERANT R 134A .
Follow safety instructions for HANDLING REFRIGERANT OIL .
Avoid contact with refrigerant and refrigerant oil.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminum screws/bolts exclusively.
Aluminum screws/bolts must be replaced each time they are released .
The end faces of aluminum 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) .
Restart engine only when air conditioning system has been correctly filled.
READ AND COMPLY WITH NOTES ON REPLACING COMPRESSOR.
Follow INSTRUCTIONS for opening and replacing parts in refrigerant circuit.
If air conditioning 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 are not included in the time value given for this work operation
- Release expansion tank and place to one side
- Remove A/C COMPRESSOR DRIVE BELT
- Remove COOLANT THERMOSTAT
Release screws (1, 2) and remove refrigerant lines.
Disconnect plug connection (3).
Tightening torque 64 52 1AZ .
Installation:
Replace sealing rings.
Use special tool 00 9 030 to mount sealing rings without damaging them.
Release screws (1, 2).
Tightening torque 64 52 3AZ .
Remove compressor towards front.
After installation:
- EVACUATE AND FILL A/C SYSTEM
- Fill and vent COOLING SYSTEM and check for leaks