17 00 009 Checking For Coolant Leaks (N73)

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NOTE:

For Special Tool identification, see COOLING SYSTEM - SPECIAL TOOLS .

Special Tools Required:

17 0 101
17 0 102
17 0 105
17 0 106

WARNING: Danger of scalding! Only perform this work after engine has cooled down.

Checking For Leaks In Cooling Circuit:

Open cap on coolant expansion tank.

Fit special tools 17 0 105/17 0 101.

Build up gauge pressure of 2 bar, wait approx. 2 minutes.

Cooling system is leak-free if pressure drop is max. 0.1 bar.

Fig 1: View Of Tester On Coolant Expansion Tank

Courtesy of BMW OF NORTH AMERICA, INC.

Checking Function Of Cap:

Fit special tools 17 0 101/17 0 102/17 0 106.

Screw sealing cap onto special tool.

NOTE: Pressure relief valve must open between 1.75 and 2.2 bar. Build up pressure with special tool 17 0 101 and observe pressure gauge to ascertain when opening pressure is achieved. Note down measured opening pressure.

After a waiting period of approx. 30 seconds, the pressure must no longer drop by more than 0.4 bar below the measured opening pressure.

Remove special tools.

Check liquid level in cooling system; if necessary: replenish.

Fig 2: Installing Sealing Cap Onto Special Tool

Courtesy of BMW OF NORTH AMERICA, INC.