Important: When removing the sealing ring, be careful not to damage the cylinder surface.
Remove the sealing ring using a plastic wedge.
Installation
After cleaning the piston and sealing ring with alcohol, dry them. Before installing the disc brake into the caliper, lightly lubricate the piston and sealing ring with grease. Insert a new sealing ring into the disc brake caliper. Install the cuff with the outer working edge of the seal on the piston.
Install the inner sealing edge of the cuff into the cylinder groove using a plastic wedge. Hold the piston with your hand.
Put on the reverse adjustment tool. Screw on the piston by turning the knurled flywheel to the right. In the case of a stiff piston, it may be possible to use an open-end wrench on the designated areas "arrow A".
Important: Pressing the piston in with the reverse adjustment tool will cancel the automatic piston adjustment in the disc brake caliper. In case of repair, it is absolutely necessary to first properly bleed the air from the disc brake calipers before installing them in the vehicle (without overlay).
Install friction linings.
Preliminary bleeding of air from the disc brake caliper
Important: To partially remove air from the wheel brake caliper, place it in a vertical position.
Open the threaded vent plug "arrow A". Pour brake fluid using a standard type air bleeder reservoir until fluid flows out of the threaded hole (connecting the brake hose) "Arrow B" - brake fluid will not start to flow out without bubbles.
Close the vent screw plug.