64 51 525 Removing and installing/replacing expansion valve (N54)
Refrigerant circuit is under high pressure!
Follow safety instructions for handling R 134a refrigerant See 6450... INSTRUCTIONS FOR HANDLING REFRIGERANT R 134A or 6450... SAFETY INSTRUCTIONS FOR HANDLING REFRIGERANT R134A .
Avoid contact with refrigerant and refrigerant oil.
Follow safety instructions for handling REFRIGERANT OIL .
Restart engine only when A/C system has been correctly filled.
Follow INSTRUCTIONS 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:
Lever out expansion rivets (1).
Unclip cable holder (2) on tension struts (3) towards top.
Release screws (1). Tightening torque, see 64 53 2AZ in 64 53 REFRIGERANT LINES AND EXPANSION VALVE . Detach refrigerant lines (2) and press slightly to one side. Installation: Replace sealing rings. Use special tool 00 9 030 to mount sealing rings without damaging them.
Release screw (1). Detach adapter plate (2) in direction of arrow. Installation: Tightening torque, see 64 53 3AZ in 64 53 REFRIGERANT LINES AND EXPANSION VALVE . Make sure bulkhead grommet (3) is correctly seated in all-round groove of adapter plate (2).
Release screws (1). Installation: Tightening torque, see 64 53 4AZ in 64 53 REFRIGERANT LINES AND EXPANSION VALVE . Carefully detach bulkhead grommet (2) from bulkhead and fold down in direction of arrow.
Detach expansion valve (1) in direction of arrow. Installation: Replace sealing rings. Use special tool 00 9 030 to mount sealing rings without damaging them. Unclip frame (2) from bulkhead and insert in groove (3) of bulkhead grommet (4). Make sure bulkhead grommet (4) is correctly seated.
After installation