64 51 580 Leak-testing evaporator

WARNING: This page is about a different variant/trim than selected.

Special tools required:

64 5 104
64 5 105
64 5 106

Necessary preliminary tasks:

Draw off refrigerant from A/C system, refer to 64 50 009 DRAWING OFF, EVACUATING AND FILLING A/C SYSTEM (R 134A)
Remove heater bulkhead, refer to 51 71 080 REMOVING AND INSTALLING/REPLACING HEATER BULKHEAD .

Release screws (1), tightening torque 64 53 2AZ. Refer to HEATING AND AIR CONDITIONING - TIGHTENING TORQUES .

Fig 1: Disconnecting Refrigerant Lines

Courtesy of BMW OF NORTH AMERICA, INC.

Disconnect refrigerant lines (2).

Installation:

Replace sealing rings.

Connect special tool 64 5 104 with special tool 64 5 105 and connect to suction line of refrigerant lines (2). Connect special tool 64 5 106 to pressure line of refrigerant lines (2).

Fig 2: Connecting Special Tools

Courtesy of BMW OF NORTH AMERICA, INC.

Tighten screws (1) to specified tightening torque 64 53 2AZ. Refer to HEATING AND AIR CONDITIONING - TIGHTENING TORQUES .

IMPORTANT: Risk of damage: Use only nitrogen pressure bottles with pressure reducers for leak-testing.

Pressurize evaporator to 15 bar slowly only. Excessively fast pressurization and pressures in excess of 20 bar may cause damage to the evaporator.

Connect nitrogen pressure bottle with pressure reducer to pressure gauge and then connect to special tool 64 5 104 (connecting hose).

NOTE:

Testing apparatus must be leakproof.
Ambient temperature and temperature of vehicle must not change during the test procedure.
Do not move the vehicle during this period.

Slowly apply test pressure of 15 bar and close nitrogen pressure bottle.

Check leak-tightness of testing apparatus and of connection to refrigerant line.

Set test pressure of 15 bar is only permitted to drop by 2 bar to 13 bar over a test period of 2 hours.

If the pressure loss is greater than 2 bar, this indicates that there is a leak in the evaporator unit with expansion valve.