steering A-B Flashcards
what is wheel lean
the ability to tilt the wheels side to side
when a grade is moving dirt with the blade set to an angle the machine will have a tendency to move to
the leading edge of the blade
how can you offset the machine being pulled in he direction of the leading edge of the blade on a motor grader
with the wheel tilt function
what is an advantage of rear wheel steering
tight maneuverability - less effort to steer the wheels
what is a disadvantage of rear wheel steering
heavy loads can cause the wheels to lose traction - cant handle high speeds
what is crab steering
allows all four tires to turn
what is circle steering
when the rear tires turn on the same track as the front tires
when a machine has a combination steering set up how are the wheels normally operated
with the steering wheel controlling one axle either the front or the back
when a combination steering system needs to be operated in crab how are the wheels controlled
the steering wheel will operate the front or the back axle while a separate switch or lever is required to operate the other
what type of steering would allow a heavily loaded machine to be operated in tight or confined areas
skid steer
what is articulation steering
when two half’s of a machine pivot at a articulation joint by hydraulic cylinders
what is a part time power steering system
is a power assist system - amount of assist depends on wheel resistance
what is full time power steering assist
provides total power steering as long as the engine is running
what is a follower valve used for
when a steering wheel is turned and held at a certain position the valve will move the cylinders to match the angle held by the steering wheel
what is another name for a full time power steering system
a hydraulic steering system or subsystem
what might be the reason for jerky hydraulic motion
aerated hydraulic oil
what is sudocavitation
aeration
what is one of the most important factors in a long lasting hydraulic system
clean hydraulic oil
what is a reversing valve
a directional control valve
what is a HMU
hydraulic metering unit
what is another name for a HMU
orbital
how do hydraulic cylinders in a steering system operate
in a push pull configuration
what is a steering cushion
used to limit the maximum turning angle
what is a neutralizer valve
used to relieve or unload hydraulic pressure just as the maximum angle is reached . this reduces the maximum impact force at the steering cushions
what are the two types of filters used
depth and screen type
is there a mechanical connection between a full time power steering system
no
why does a co-ordinated steering system on a loader require less effort
because the rear wheels follow in the same path as the front wheels so they do not have to break new ground during the steering process
what is another name for the tractor scraper articulated hitch assembly
the goose neck
never use your hand to check for
hydraulic oil leaks
why must hydraulic oil be raised to proper operating temp before testing can begin
to eliminates any uncertainty during testing due to thick oil, leakage and or poor circulation
what must you do to systems containing hydraulic accumulators
properly discharge the system
when working in the articulation hitch area what should be installed
lock bar or safety bar
when removing pivot pin caps you should never use
a hammer - mating surfaces can become deformed
what does the tie rod provide in a steering system
proper toe adjustment
what might have to be adjusted before tie rod end play can be determined
loose wheel bearing may be interpreted as tie rod endplay
when disconnecting articulation hitch what should be considered before removal
support the front and rear of the machine with stands to prevent them from dropping when disconnected
what are the two types of directional control valves
HMU - Spool steering valve
hydraulic skid steering system typically involves
a closed loop system
what is another name for the swash plate in a hydraulic piston pump
cam plate
the ability of the hydraulic cooler is greatly dependant on
the amount of airflow through the cooler assembly
the only way to completely remove all contaminants from the hydraulic steering system is to
remove disassemble and thoroughly clean and flush
if the machine steering system is unsafe and movement of the machine would be a danger you should not
take it out for a road test
even if the machine is equipped with quick couplers
you should release the system pressure and loosen the quick coupler seal caps very slowly in case system pressure exists
