Subaru Legacy/Outback

1999-2003 of release

Repair and operation of the car



Subaru of Legasi, Autbek
+ Cars Subaru Legacy, Outback
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling systems, heating
+ Power supply system and release
+ Electric equipment of the engine
+ Manual box and differential
+ Automatic transmission
+ Coupling
- Brake system
   Specifications
   Brake mechanisms of lobbies and back wheels - the general information
   The parking brake - a design and the principle of functioning
   Pressure valve limiter - a design and the principle of functioning
   Antiretractable system - the device, the principle of functioning and a precautionary measure
   System of anti-blocking of brakes (ABS) - the general information, the principle of functioning
   System of dynamic stabilization (VDC) - the general information, the principle of functioning
   Check of a state replacement of blocks of disk brake mechanisms of forward wheels
   Removal, check of a state and installation of forward brake disks
   Removal, service and installation of disk brake mechanisms of forward wheels
   Check of a state and replacement of blocks of disk brake mechanisms of back wheels
   Removal, check of a state and installation of back brake disks
   Removal, service and installation of disk brake mechanisms of back wheels
   Removal, service and installation of the main brake cylinder (MBC)
   Removal, installation and check of serviceability of functioning of the vacuum amplifier of brakes
   Removal, installation and check of serviceability of functioning of the valve limiter of pressure
   Replacement of brake fluid
   Pumping of a hydraulic path of brake system
   Check of a state and replacement of flexible brake hoses
   Check of a state and replacement of tubes of a brake path
   Removal, service, installation and adjustment of a pedal of a foot brake
   Removal, check of a state, installation and adjustment of the sensor switch of stoplights
   Removal, installation, check of a state and adjustment of the lever of the drive of the parking brake
   Removal, check of a state and installation of elements of the hummock drive of the parking brake
   Removal, installation and adjustment of the mechanism of the parking brake
   Removal, installation, check of a state and adjustment of components of the antiretractable device
   Removal, installation and check of serviceability of functioning of assembly of the module of the ABS management/hydromodulator
   Check of sequence of operation of valves of the ABS hydromodulator
   Removal, installation and check of serviceability of functioning of forward wheel ABS sensors
   Removal, installation and check of serviceability of functioning of back wheel ABS sensors
   Removal, installation and check of a condition of rotors of wheel sensors
   Removal, installation and diagnostics of the sensor of overloads (G-sensor)
   Problem diagnostics of ABS
   Removal, installation and adjustment of the module of management of VDC
   Removal, installation and check of serviceability of functioning of the VDC hydromodulator
   Check of sequence of operation of valves of ABS and VDC hydromodulators
   Removal, installation and check of serviceability of functioning of the sensor of withdrawal / cross overloads
   Removal, installation and check of serviceability of functioning of the sensor of an angle of rotation of a steering wheel of VDC
   Removal, installation and check of serviceability of functioning of wheel sensors with rotors
   Removal, installation and check of serviceability of functioning of the switch of deactivation of VDC (VDC OFF)
   Problem diagnostics of VDC
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment









d9f1bda0


Pressure valve limiter - a design and the principle of functioning

Chart of operation of the valve limiter


Principle of functioning of the valve limiter

1 — To wheel cylinders of back brake mechanisms
2 — From GTTs
3 — the Saddle

4 — the Spring
5 — the Piston
6 — the Valve


The valve limiter serves for prevention of premature blocking of back wheels of the car at sharp braking as a result of transfer of the car center of gravity forward. The valve provides decrease in a pressure of hydraulic liquid in brake contours of back wheels at achievement with pressure in the main brake cylinder of some critical value.

With a pressure in GTTs below a critical point the working piston of assembly is wrung out by a spring to the left, leaving a valve saddle free and pressure of hydraulic P3 liquid in wheel cylinders back brake mechanisms remains equal to the working pressure of the main brake cylinder ("P2").

Rise in pressure of "P2" to critical value leads to generation of effort of "f2" (working section of the piston "A" is selected so that effort arose in a critical point) which is wringing out the piston to the right with overcoming of force of resistance of a spring of "F". The saddle of valvate assembly is also displaced to the right, blocking the section of the channel through passage of supply of hydraulic liquid in wheel cylinders of back brake mechanisms. At the moment just before that as supply of liquid in contours of back wheels stops, pressure of "P2" slightly exceeds pressure of "P3", comparison of pressure leads to a full overshoot of the valve and pressure decrease in back brake mechanisms concerning pressure in wheel cylinders of forward supports. The valve continues to remain in a running cycle until the effort enclosed to a pedal of a foot brake is not weakened.