Pre-tensioning the timing chain with the special tool

Ensure that the timing chain is correctly pre-tensioned with the special tool 2 455 654.
The pin (1) must close flush with the housing (2).

Courtesy of BMW OF NORTH AMERICA, INC.
Ensure that the timing chain does not have too low of a pre-tension.
The pre-tension is too low if the pin (1) of the special tool 2 455 654 does not close flush with the housing (2).

The timing chain is not pre-tensioned correctly.

Courtesy of BMW OF NORTH AMERICA, INC.
Ensure that the timing chain does not have too high a pre-tension.
The pre-tension is too high if the pin (1) of the special tool 2 455 654 does not close flush with the housing (2).

The timing chain is not positioned correctly.

Courtesy of BMW OF NORTH AMERICA, INC.