Notes on externally invisible brake fluid loss - AH42.10-P-9406-02AK
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MODEL 169, 245
In the event of brake fluid loss which is not visible from outside, check whether there is brake fluid ingress into 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.
There must be no more than 100 cm 3
brake fluid in the brake booster.
Otherwise 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. When the brake booster is installed no brake fluid can enter the reaction disk or the plate valve up to 100 cm 3
.