Sequence of works
1. Unscrew the union nut securing the brake hose to the pipeline. While doing this, hold it by the splines of the brake hose to prevent it from turning.
2. If the nut is rusted to the pipeline and it turns when unscrewed, it should be replaced in any case. Thin-walled pipeline tubes break easily.
3. To do this, cut the pipeline near the fastening and unscrew the nut with a hex head.
4. If the new pipeline needs to be bent slightly, the bend must have a large radius. Otherwise, the thin pipeline will break.
5. Hold the inner side of the tube with your fingers while bending. Do this along the entire radius of the required bend line.
6 Don't forget about protective hoses and gaskets (if they exist).
7. Lay the new pipeline and secure it in the holders.
Original source of information: MercedesMan.ru
8. Observe the tightening torques for the hose to the brake pipe – 15 Nm, the pipe to the brake master cylinder, distributor – 15 Nm.
9. Bleed the brake system.