Notes On Externally Invisible Brake Fluid Loss - AH42.10-P-9406-02GZ
WARNING: This page does not describe the selected car, but rather 27 other vehicles, including the 2019 Mercedes-Benz GLE63 S AMG, 2019 Mercedes-Benz GLE63 AMG, 2019 Mercedes-Benz GLE43 AMG, 2019 Mercedes-Benz GLE400, and 2018 Mercedes-Benz GLE63 S AMG. However, it is still accessible from the selected car via links, so may be relevant.
MODEL 164, 166, 292
In the case of brake fluid loss which is not visible, it should be checked whether brake fluid has entered the brake booster through a leaking secondary seal in the tandem master brake cylinder:
- Remove master brake cylinder.
- Draw off any brake fluid which has entered and empty into a measuring beaker.
If there are more than 100 cm3
of brake fluid in the brake booster, the brake booster must be replaced.
The power diaphragm in the brake booster is resistant to brake fluid, but not the reaction disk and the poppet valve in the master control unit.
Brake fluid must therefore only be suctioned off when the brake booster is installed. With a quantity of 100 cm3 , brake fluid cannot get to the reaction disk or poppet valve when the brake booster is installed.