6. STEERING & BRAKES 1. Co Comp mpon onen ents ts La Layo yout ut 2. Opera rattion 3. Testing & Adjusting Adolfo OCTOBER 1997
P a g e : 6 - 2
STEERING SYSTEM COMPONENTS STEERING PUMP
PILOT PUMP
PILOT PILOT RELIEF FILTER VALVE
DUAL PILOT CHECK VALVE
STEERING PILOT CONTROL VALVE
NEUTRALIZER VALVES
STEERING CONTROL VALVE
PILOT SYSTEM
P a g e : 6 - 3
STEERING AND BRAKE TANK
MAIN HYDRAULIC SYSTEM
STEERING CYLINDERS
COMMON TO MAIN AND PILOT SYSTEMS
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
CONTROL LEVER
STEERING HYDRAULIC SYSTEM HOLD PILOT CONTROL VALVE PILOT PUMP
NEUTRALIZER VALVE
FILTER
PILOT RELIEF VALVE
CHECK VALVE
STEERING PUMP
COOLER
NEUTRALIZER VALVE
DUAL CHECK VALVE
CHECK VALVE CONTROL VALVE
STEERING CYLINDERS TANK
P a g e : 6 - 3
CONTROL LEVER
STEERING HYDRAULIC SYSTEM HOLD PILOT CONTROL VALVE PILOT PUMP
NEUTRALIZER VALVE
FILTER
PILOT RELIEF VALVE
CHECK VALVE
STEERING PUMP
COOLER
NEUTRALIZER VALVE
DUAL CHECK VALVE
CHECK VALVE CONTROL VALVE
STEERING CYLINDERS TANK
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
STEERING PILOT PUMP
IMPLEMENT FIXED PUMP
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
STEERING PILOT PUMP
STEERING PUMP COMPENSATOR VALVE
Page:
6-4
IMPLEMENT FIXED PUMP
MAIN STEERING PUMP
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
LEFT FRAME
PILOT RELIEF VAL ALVE VE
Page:
6-5
STEERING PILOT FILTER
STEERING CONTROL VALVE
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
STICK CONTROL LEVER
STIC STEERING AND TRANSMISSION LOCK LEVER
Page:
6-6
STEERING PILOT CONTROL VALVE
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
NEUTRALIZER NEUTRALI ZER VAL ALVES VES
PARKING BRAKE VALVE
ADJUSTABLE STRIKERS
Page:
6-7
P a g e : 6 - 8
STEERING PUMP AND COMPENSATOR VALVE LOW PRESSURE STANDBY SWASHPLATE MINIMUM ANGLE STOP MAXIMUM ANGLE STOP
SMALL ACTUATOR PISTON
CONPENSATOR VALVE
LARGE ACTUATOR PISTON
FROM STEERING CONTROL VALVE
PRESSURE COMPENSATOR SPOOL
FLOW COMPENSATOR SPOOL
P a g e : 6 - 9
CHARGE PUMP
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
STEERING PUMP AND COMPENSATOR VALVE UPSTROKE SWASHPLATE MINIMUM ANGLE STOP MAXIMUM ANGLE STOP
SMALL ACTUATOR PISTON
CONPENSATOR VALVE
LARGE ACTUATOR PISTON
FROM STEERING CONTROL VALVE
FLOW COMPENSATOR SPOOL
PRESSURE COMPENSATOR SPOOL
CHARGE PUMP
P a g e : 6 - 9
STEERING PUMP AND COMPENSATOR VALVE UPSTROKE SWASHPLATE MINIMUM ANGLE STOP MAXIMUM ANGLE STOP
SMALL ACTUATOR PISTON
CONPENSATOR VALVE
LARGE ACTUATOR PISTON
CHARGE PUMP
FROM STEERING CONTROL VALVE
FLOW COMPENSATOR SPOOL
PRESSURE COMPENSATOR SPOOL
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
SELECTOR VALVE
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
COMPONENTS
SELECTOR VALVE
CROSSOVER RELEF VALVE
Page:
6-10
STEERING CONTROL VALVE
P a g e : 6 - 1 1
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
HOLD DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
RIGHT LEFT NEUTRALIZER NEUTRALIZER
PILOT PUMP
TANK
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 2
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
GRADUAL RIGHT TURN DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
RIGHT LEFT NEUTRALIZER NEUTRALIZER
TANK
PILOT PUMP
P a g e : 6 - 1 2
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
GRADUAL RIGHT TURN DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
RIGHT LEFT NEUTRALIZER NEUTRALIZER
PILOT PUMP
TANK
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 3
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
SHARP RIGHT TURN DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
RIGHT LEFT NEUTRALIZER NEUTRALIZER
TANK
PILOT PUMP
P a g e : 6 - 1 3
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
SHARP RIGHT TURN DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
RIGHT LEFT NEUTRALIZER NEUTRALIZER
PILOT PUMP
TANK
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 4
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
GRADUAL RIGHT TURN SECONDARY STEER DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
LEFT RIGHT NEUTRALIZER NEUTRALIZER
TANK
PILOT PUMP
P a g e : 6 - 1 4
STEERING CYLINDERS
STEERING SYSTEM STEERING CONTROL VALVE
GRADUAL RIGHT TURN SECONDARY STEER DIVERTER VALVE
SHUTTLE VALVE LINE RELIEF VALVE
CONTROL SPOOL
SECONDARY RELIEF VALVE
BACK-UP RELIEF VALVE
PRESSURE REDUCING VALVE
COMPENSATOR VALVE
SECONDARY PUMP
DUAL CHECK VALVE STEER CONTROL VALVE
PILOT RELIEF VALVE
STEER LEVER
FILTER COOLER
SELECTOR VALVE
STEERING PUMP
FLUID SAMPLING PORT
LEFT RIGHT NEUTRALIZER NEUTRALIZER
TANK
PILOT PUMP
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 5
BRAKE SYSTEM COMPONENTS BRAKE PUMP
BRAKE ACCUMULATORS
REAR SERVICE BRAKES
PARKING BRAKE VALVE
STEERING AND BRAKE TANK
Serv Se rvic ice e Br Brak ake e Com ompo pone nent nts s
PARKING BRAKE
PARKING BRAKE LEVER
MANIFOLD
Par arki king ng Br Brak ake e Com ompo pone nent nts s
SERVICE BRAKE PEDALS
SERVICE BRAKE VALVE
FRONT SERVICE BRAKES
Shar Sh ared ed by Ser ervi vice ce an and d Pa Park rkin ing g Sy Syst stem ems s
P a g e : 6 - 1 5
BRAKE SYSTEM COMPONENTS BRAKE PUMP
BRAKE ACCUMULATORS
REAR SERVICE BRAKES
PARKING BRAKE VALVE
STEERING AND BRAKE TANK
Serv Se rvic ice e Br Brak ake e Com ompo pone nent nts s
PARKING BRAKE
PARKING BRAKE LEVER
MANIFOLD
Par arki king ng Br Brak ake e Com ompo pone nent nts s
SERVICE BRAKE PEDALS
SERVICE BRAKE VALVE
FRONT SERVICE BRAKES
Shar Sh ared ed by Ser ervi vice ce an and d Pa Park rkin ing g Sy Syst stem ems s
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 6
BRAKE HYDRAULIC SYSTEM BRAKE VALVE REAR BRAKE ACCUMULATOR FRONT BRAKE ACCUMULATOR
MANIFOLD
MANIFOLD
CHECK VALVE PUMP CHECK VALVE PARKING BRAKE VALVE TANK
PARKING BRAKE
REAR BRAKE
FRONT BRAKE
P a g e : 6 - 1 6
BRAKE HYDRAULIC SYSTEM BRAKE VALVE REAR BRAKE ACCUMULATOR FRONT BRAKE ACCUMULATOR
MANIFOLD
MANIFOLD
CHECK VALVE PUMP CHECK VALVE PARKING BRAKE VALVE
PARKING BRAKE
REAR BRAKE
FRONT BRAKE
TANK
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
BRAKE SYSTEM COMPONENTS BRAKE PUMP
PUMP SERVO VALVE
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
BRAKE SYSTEM COMPONENTS BRAKE PUMP
DECK PLA PL ATE
Page:
6-17
PUMP SERVO VALVE
ACCUMULATORS
P a g e : 6 - 1 8
BRAKE PUMP LOW PRESSURE CONTROL PISTON
SPRING
PUMP SERVO VALVE BARREL
CONTROL PISTON PASSAGE
OUTLET PASSAGE
DRIVE SHAFT INLET PASSAGE PISTON ASSEMBLY
SWASHPLATE
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 1 9
PUMP SERVO VALVE LOW LO W BR BRAK AKE E SY SYST STEM EM PR PRES ESSU SURE RE
HIGH HI GH BR BRAK AKE E SY SYST STEM EM PR PRES ESSU SURE RE TO CONTROL FROM PUMP OUTLET PISTON
TO CONTROL FROM PUMP OUTLET PISTON ADJUSTMENT BOLT
LOCKNUT PRESSURE COMPENSATOR SPOOL
ADJUSTMENT BOLT
LOCKNU LOC KNUT T
PRESSU PRE SSURE RE COM COMPEN PENSAT SATOR OR SPO SPOOL OL
P a g e : 6 - 1 9
PUMP SERVO VALVE LOW LO W BR BRAK AKE E SY SYST STEM EM PR PRES ESSU SURE RE
HIGH HI GH BR BRAK AKE E SY SYST STEM EM PR PRES ESSU SURE RE TO CONTROL FROM PUMP OUTLET PISTON
TO CONTROL FROM PUMP OUTLET PISTON ADJUSTMENT BOLT
ADJUSTMENT BOLT
LOCKNUT PRESSURE COMPENSATOR SPOOL
LOCKNU LOC KNUT T
PRESSU PRE SSURE RE COM COMPEN PENSAT SATOR OR SPO SPOOL OL
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 2 0
BRAKE PUMP HIGH PRESSURE CONTROL PISTON
SPRING
PUMP SERVO VALVE BARREL
CONTROL PISTON PASSAGE
OUTLET PASSAGE
DRIVE SHAFT INLET PASSAGE PISTON ASSEMBLY
SWASHPLATE
P a g e : 6 - 2 0
BRAKE PUMP HIGH PRESSURE CONTROL PISTON
SPRING
PUMP SERVO VALVE BARREL
CONTROL PISTON PASSAGE
OUTLET PASSAGE
DRIVE SHAFT INLET PASSAGE PISTON ASSEMBLY
SWASHPLATE
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
BRAKE SYSTEM COMPONENTS
SERVICE BRAKE VAL ALVE VE
PARKING BRAKE VALVE
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
BRAKE SYSTEM COMPONENTS
SERVICE BRAKE VAL ALVE VE
Page:
6-21
PARKING BRAKE VALVE
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
BRAKE OIL LINE
BRAKE SYSTEM COMPONENTS
BRAKE COOLING OIL LINE
PARKING BRAKE
Page:
6-22
SERVICE BRAKE HOUSING
SECONDARY STEERING PUMP
P a g e : 6 - 2 3
BRAKE HYDRAULIC SYSTEM SERVICE BRAKE OFF / PARKING BRAKE ON
BRAKE VALVE
REAR BRAKE ACCUMULATOR FRONT BRAKE ACCUMULATOR
MANIFOLD
MANIFOLD
CHECK VALVE PUMP CHECK VALVE PARKING BRAKE VALVE
PARKING BRAKE
REAR BRAKE
FRONT BRAKE
TANK
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
P a g e : 6 - 2 4
BRAKE HYDRAULIC SYSTEM SERVICE BRAKE ON / PARKING BRAKE OFF
BRAKE VALVE
REAR BRAKE ACCUMULATOR FRONT BRAKE ACCUMULATOR
MANIFOLD
MANIFOLD
CHECK VALVE PUMP CHECK VALVE PARKING BRAKE VALVE TANK
PARKING BRAKE
REAR BRAKE
FRONT BRAKE
P a g e : 6 - 2 4
BRAKE HYDRAULIC SYSTEM SERVICE BRAKE ON / PARKING BRAKE OFF
BRAKE VALVE
REAR BRAKE ACCUMULATOR FRONT BRAKE ACCUMULATOR
MANIFOLD
MANIFOLD
CHECK VALVE PUMP CHECK VALVE PARKING BRAKE VALVE
PARKING BRAKE
REAR BRAKE
FRONT BRAKE
TANK
P a g e :
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
AXLE COOLING SYSTEMS
6 - 2 5
BRAKE
REAR AXLE
AXLE MANIFOLD
BRAKE
AXLE MANIFOLD
FRONT AXLE
COOLER BRAKE
BRAKE
COOLER RELIEF VALVE RELIEF VALVE
REAR PUMP
FRONT PUMP
P a g e :
AXLE COOLING SYSTEMS
6 - 2 5
BRAKE
REAR AXLE
AXLE MANIFOLD
BRAKE
FRONT AXLE
AXLE MANIFOLD
COOLER BRAKE
BRAKE
COOLER RELIEF VALVE RELIEF VALVE
REAR PUMP
FRONT PUMP
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
LAB EXERCISES Lab A: Steering System Component Identification Identification Quiz Worksheet Directions: Use this worksheet during the presentation to take notes on the function and location of each component. During the lab exercise locate the components. Component
Location on the Machine
Dual check valves
___________________________________
Steering pump
___________________________________
Steering and brake oil tank
___________________________________
Steering pilot pump
___________________________________
Steering pilot relief valve
___________________________________
C H A P T E R : S T E E R I N G & B R A K E S
9 9 2 G W H E E L L O A D E R
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
LAB EXERCISES Lab A: Steering System Component Identification Identification Quiz Worksheet Directions: Use this worksheet during the presentation to take notes on the function and location of each component. During the lab exercise locate the components. Component
Location on the Machine
Dual check valves
___________________________________
Steering pump
___________________________________
Steering and brake oil tank
___________________________________
Steering pilot pump
___________________________________
Steering pilot relief valve
___________________________________
Steering pilot control valve
___________________________________
Steering pilot and brake filter
___________________________________
Main control valve
___________________________________
Oil cooler
___________________________________
Steer cylinders
___________________________________
Neutralizer valve
___________________________________
Pressure reducing valve
___________________________________
Secondary pump
___________________________________
Selector and pressure control valve
___________________________________
Page:
6-26
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
LAB EXERCISES Lab B: Steerin Steering g System Operational Operationa l Tests Workshe orksheet et Steering Time Check: 1. Run the test three times. 2. Compare the average time to the Service Manual specification.
Oil Temp ____°C
1st Test
2nd Test
3rd Test
Averag veragee
Cycle Time Specification STEERING SYSTEM PRESSURE SPECIFICATION
ACTUAL
Pilot Oil Pressure Back up Relief Valve Left Turn Back up Relief Valve Right Turn Pressure Compensator Valve Valve Margin Pressure NEUTRALIZER STRIKER ADJUSTMENT SPECIFICATION
ACTUAL
ADJUSTMENT
Right Stop Left Stop Lab C: Brake System Operational Tests Tests Workshe Worksheet et BRAKE SYSTEM PRESSURE SPECIFICATION Brake Pump Compensator Valve Service Brake Control Valve Parking Brake Control Valve Page:
6-27
ACTUAL
992G WHEEL LOADER CHAPTER : STEERING & BRAKES
LAB EXERCISES Lab D: Brake System and Brake Cooling System Component Identification Identification Quiz Worksheet Directions: Use this worksheet during the presentation to take notes on the function and location of each component. During the lab exercise locate the components. Component
