64 51... Leak-testing evaporator: Notes

WARNING: This page is about a different car, the 2011 BMW 750xi, 2011 BMW 750Lxi, 2010 BMW 750xi, and 2010 BMW 750Lxi. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

WARNING: Comply with the standard national safety regulations on handling nitrogen.
Ensure that employees are advised of how to handle pressurized vessels and nitrogen gas correctly (danger of asphyxiation). For this purpose, follow the notes and instructions in the technical safety specifications available from the gas supplier.

Necessary preliminary tasks:

Remove EXPANSION VALVE

NOTE: Graphic similar.

Replace sealing rings.

Use special tool 00 9 030 to mount sealing rings without damaging them.

Fig 1: Identifying Sealing Rings

Courtesy of BMW OF NORTH AMERICA, INC.

Screw the special tool 64 5 126 to the retaining clip of the expansion valve.

Tightening torque 64 53 9AZ .

NOTE: The original screws of the expansion valve are too long for the special tool 64 5 126 and can therefore not be used!
Shorter screws of the same type which are approx. 30 mm in length must be used.

Fig 2: Installing Special Tool (64 5 126) To Expansion Valve Retaining Clip

Courtesy of BMW OF NORTH AMERICA, INC.

Connect special tool 64 5 121 to special tool 64 5 126 .

IMPORTANT: Risk of damage: Use only nitrogen pressure bottles with pressure reducers for leak-testing.
Pressurize evaporator to 10 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 5 121 (connecting hose).

NOTE:

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

Apply test pressure of 10 bar slowly and close nitrogen pressure bottle.

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

Set test pressure of 10 bar is only permitted to drop by 2 bar to 8.5 bar over a test period of 1.5 hours.

If the pressure loss is greater than 1.5 bar, this indicates that there is a leak in the evaporator unit.

WARNING: After leakage check, unscrew special tool 64 5 121slowly from special tool 64 5 126 to reduce pressure.