Steering Systems Flashcards
What are the functions of a steering system?
- provides control of front wheels
- Maintains correct amount of effort needed to turn front wheels
- transmits road feel to driver hands
- absorbs most of shocking going to steering
- allows for suspension travel
Describe the steering wheel.
Used by drive to rotate steering shaft
Describe the steering shaft.
Transfers steering wheel motion to the steering gear box
Describe the steering column.
Supports the steering wheel and shaft
Describe the steering gear box.
Changes turning motion into straight left and right motion
Describe the steering linkage
Connects the steering gear box to the steering knuckles
Describe the ball joints
Allows control arms to move
Describe the pinion gear on a rack and pinion steering.
Rotated by steering wheel and shaft, it’s teeth mesh with the ones on the rack
Describe the gear housing on a rack and pinion steering.
Holds the pinion gear and rack assembly
Describe the Tie Rods in a rack and pinion steering.
Inner and outer tie rods connect to the steering knuckle
Describe worm type steering.
Steering linkage have several parts that connect steering gear box to the steering knuckles.
What do worm type gearboxes usually have?
A pitman arm, idler arm, centre link, and the tie rod ends
Describe a pitman arm.
Splined to the output shaft of the gearbox and the other end of the centre link
Describe the centre link.
Steel bar connecting the left and right side to the pitman arm and idler arm
Describe the idler arm.
Connected to the frame on the passenger side and supports the centre link
Describe the ball sockets.
Provides a swivel connection between two parts
Describe the tie rod assembly.
Allows for suspension action and adjustment for wheel alignments
Describe the integral power steering system.
Has the hydraulic piston inside the steering gear box
Describe the external power steering system (linkage type).
A power steering system that uses a power ram bolted to the frame and to the centre link.
Describe a power cylinder
Hydraulic cylinder, steel tube, machines, supporting the rack inside the housing
Describe the power piston
Hydraulic double acting piston formed on the rack
Describe the hydraulic lines
Steel tubing connecting the spool valve to each side of the hydraulic piston
Describe the control valve
Rotary or spool valve that controls the fluid to each side of the piston
Describe the pressure relief valve.
Controls the maximum oil pressure usually you can hear it working on full lock turns, if this sticks open there is no power assist
Describe the high pressure feed hose.
Connects from the power steering pump to the steering gear box
Describe the lower pressure return hose.
Connects from the steering gear box through a fluid cooler back to the reservoir
What are the two types of power steering hoses?
High pressure feed hose, low pressure return hose
What do power systems use to assist with the steering action?
Engine driven pump and hydraulic system, new vehicles use electric motors.
High pressure fluid to the piston cylinder assembly is supplied by?
The steering pump
What is the purpose of a control valve in a power steering system?
Directs pressured fluid to one or the other end of the piston in the gearbox
The piston slide in the cylinder under _________
Pressure
What is the purpose of a power steering system?
Assist in movement of the steering components and front wheels as the vehicle steering wheel is turned
At slow speeds how are the wheels turned?
Rear wheels are then in the opposite direction of front wheels
At fast speeds how are the wheels turned?
All four wheels are turned In the same direction
Describe a wheel alignment.
Purpose is to make the tires roll without scuffing, slipping, or dragging.
What are the 6 fundamental angles for a proper wheel alignment?
Caster Camber Toe Steering axis Toe out on turns Tracking
Describe the caster angle
Forward or rearward tilt of the steering knuckle
Describe positive caster
The steering axis will tilt towards the driver
Describe negative caster
The wheels will be easier to turn, wheels will tend to swivel and follow road imperfections
How is caster measured?
In degrees
Describe camber
Inward or outward tilt of wheel
What does camber control.
Controls where the tire touches to pavement
What is positive camber
The outward tilt
What is negative camber
The inward tilt
Describe the toe angle
The difference between the left and right wheel at the front
What is toe in?
The front wheels are closer together than the rear wheels
What is toe out?
The rear wheels are closer together than the front wheels
What is the purpose of steering angle inclination?
It aids directional control, it’s not adjustable but can be used to determine if something is bent
Describe under steering
When vehicle is slow to respond to steering changes in a turn. Rear tires retain traction front skid/slip
Describe oversteer
Front maintain traction but rear tend to skid/slip sideways on tight turns
Describe tracking
To insure to the rear wheels follow in the tracks of the front wheels straight ahead
What is another word for improper tracking?
Also called dog tracking
Describe setback
When one side wheels are closer together than the other side, Frame damage, bent or Broken parts
