Constantly monitor the serviceability of the service brake system, adjust it in a timely manner and eliminate any malfunctions
Regularly check the fluid level in the reservoirs of the master brake cylinder and top up if necessary.
The level should be 15–20 mm below the top edges of the filling holes.
Watch the tightness of the connections of the hydraulic drive pipelines.
Check the condition of the pipelines, the reliability of the fastening of the tubes on the frame and rear axle.
During inspections, make sure that the tubes and flexible hoses are not damaged.
Replace damaged tubes and hoses with new ones.
Fig. 1. Pressure regulator
For seasonal maintenance, check the operation of the pressure regulator.
Clean the regulator from dirt and check the reliability of its fastening.
By visual inspection, make sure that the regulator and its drive parts are not damaged, there are no brake fluid leaks and gaps in the connection of the stand with the elastic lever and the bracket on the rear axle (Fig. 2).
When you press the brake pedal, piston 1 (see Fig. 1) of the pressure regulator should move out of the housing by 1.7–2.3 mm.
A lack of piston stroke, as well as insufficient or excessive piston stroke, indicate a malfunction of the regulator or its actuator.
When inspecting the hydraulic drive, pay attention to the location of the plastic (control) plug 17 and the absence of brake fluid leakage from under it.
In the normal state, the plug should be recessed into the hole in the regulator body until it stops.
The protrusion of the plug from the hole and the leakage of brake fluid mean the loss of tightness of the sealing rings 11 and, as a result, the efficiency of the regulator.
Fig. 2. Pressure regulator drive
If necessary, check the reliability of the vacuum booster, flush or replace the air filter of the booster.
Periodically remove the brake drums and clean the parts of the brake mechanisms from dirt.
In the summer and when driving on muddy roads, clean more often.
When removing the brake drum, make sure that there are no leaks from the wheel brake cylinders, as well as that the wheel cylinders are securely fastened to the shields.
Pay attention to the condition of the protective caps of the wheel cylinders, the degree of wear of the friction linings, as well as the condition of the brake drum.
In case of “oiling” the surfaces of the linings, clean them with sandpaper.
With the hubs removed, tighten the bolts securing the brake shields.
Regularly flush the hydraulic drive and fill it with fresh brake fluid.
To thoroughly flush the hydraulic drive, disassemble the main and wheel brake cylinders, the pressure regulator, and blow the pipelines with compressed air.
Keep clean when disassembling the cylinders.
Wash the rubber and metal parts of the cylinders in clean brake fluid.
Do not use kerosene or gasoline, as this will cause swelling of the rubber parts and failure of the brake system.
During assembly, it is recommended to lubricate the working parts of the cylinders with brake fluid.