Dismantling the brake cylinder consists in the following steps.
■ Remove the brake drum and shoes as described in the previous section.
■ Unscrew the brake hose connected to the cylinder.
■ Unscrew the cylinder fixing screws and remove the cylinder from the backing plate. The possible repair of the cylinder includes the following scope of activities.
■ Remove the rubber covers on both ends of the cylinder.
■ Remove the pistons (2); they can be blown out with compressed air supplied to the opening via the brake hose.
■ Remove the sealing rings (3) and a spring (4) with cups. All parts must be in working order. The working surfaces of the pistons and the cylinder must not have any grooves, and the clearance of the assembly must not exceed 0,15 mm.
The cylinder is installed in the reverse order. The inside of the cylinder, new O-rings and pistons must be lubricated with brake fluid before reassembling.
After mounting the cylinder, Bleed the system from the brake shoes and brake drum.
