17 00 009 Checking For Coolant Leaks (N62)

WARNING: This page is about a different car, the 2007 BMW 550i and 2006 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

WARNING:

Danger of scalding!

Only perform this work after engine has cooled down.

NOTE:

Illustrations show M54:

Checking pressure drop in cooling system:

Open cap on coolant expansion tank. Fit special tool 17 0 101 /17 0 113 .

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

Cooling system is impervious to leaks if pressure drop is max. 0.1 bar.

Fig 1: Identifying Special Tools (17 0 101, 17 0 102, and 17 0 113)

Courtesy of BMW OF NORTH AMERICA, INC.

Checking pressure relief valve in cap:

NOTE:

Coolant residue can cause the pressure relief valve in the cap to stick, therefore repeat the check procedure on the cap 2-3 times.

Screw cap (1) onto special tool 17 0 114 .

Build up pressure with special tool 17 0 101 (hand pump); observe pressure gauge to ascertain when opening pressure is achieved.

Opening pressure of pressure relief valve.

Fig 2: Identifying Special Tools (17 0 101 / 17 0 114)

Courtesy of BMW OF NORTH AMERICA, INC.