201-00-3 Suspension System
Diagnosis and Test (Continued)
Inspection and Confirmation
Vibration diagnosis procedures usually begin with
road test. The road test and the interview with clients
(if possible) can provide a great deal of information
for confirming failure cause.
During the road test, the automobile should be running
on a smooth road without slopes. If obvious fluttering
occurs, please record the following contents:
– The speed when the automobile flutters.
– The type of automobile vibration occurring within
a certain speed scope.
– The impact on vibration when the engine torque,
the automobile speed and the engine rotating
speed change.
– The type of vibration sensitivity - torque
sensitivity, automobile speed sensitivity or
sensitivity of the engine rotating speed.
If the road test shows that the automobile vibration is
related to the automobile tyre, please use tyre wear
status table to inspect the failure cause at a fixed point.
If the road test indicates that abnormal sound of the
tyre occurs but the automobile is vibrationless;
abnormal sound of the tyre is caused by contact of the
tyre and the ground.
Utilize the following contents to find out the vibration
cause:
Torque Sensitivity
This indicates that noise can be weakened or
increasingly vibrate with speedup, slowdown,
skidding or keeping uniform speed of the vehicle.
Automobile Speed Sensitivity
This indicates that automobile speed sensitivity
always occurs within a fixed vehicle speed scope, and
cannot be affected by the automobile torque, the
engine rotating speed or the transmission case.
Sensitivity of the Engine Rotating Speed
This indicates that fluttering can be caused when
different gears of the transmission case are chosen, the
engine rotating speed is constant, and the automobile
is at different speeds. Fluttering can also be caused by
speeding up or slowing down when the transmission
case of the automobile is at the position of neutral gear
or the four wheels hang up and the neutral gear is put
into. If the situation is related to the engine rotating
speed, the vibration cause has nothing to do with tyres.
Ball Head of the Tie Rod
Note: Before the inspection or positioning of the front
suspension, inspect the ball head of the tie rod for
abrasion at first.
1. Inspect air pressure of four tyres.
2. Hoist the automobile. See Section 100-02 for
relevant information. Inspect whether the ball
head and the bracket of the front suspension are
loose, abraded or damaged. See the section of
Ball Head of the Lower Cross Arm for relevant
information. Tighten all the loose nuts according
to torque specifications. When parts are required
to be replaced, see Section 201-01.
3. Inspect whether connection between the steering
mechanism and the tie rod is loose. Tighten them
according to the torque specifications. If the ball
head of the tie rod is abraded or broken, replace it.
See Section 211-02 for relevant information.
4. Disassemble the front tyres. Inspect run-out amount
of the tyre and single-edge abrasion. Perform
dynamic balancing of the tyre.
5. Inspect the suspension device and the working
situation of the accessories. See the section of
Inspection of the Suspension Assembly. Jamming
of the suspension assembly would cause that the
automobile cannot achieve the normal position,
and thereby would impact on front wheel
alignment.
Inspection of the Ball Head of the Lower Cross
Arm
1. Hoist the automobile. See Section 100-01 for
relevant information.
2. Tightly grip the outer end of the lower cross arm,
and try to move vertically to observe if there is
movement. Free movement is generally followed
by the sound of click, which shows that the ball
head of the lower cross arm has been damaged.
3. If free movement occurs, replace the ball head.
See Section 201-01 for relevant information.
4. After the ball head is replaced, front wheel
alignment shall be performed. See the section of
Common Procedures for relevant information.
Inspection of the Suspension Device
All the automobiles are equipped with low pressure
gas-hydraulic suspension devices which can not be
adjusted or refilled.
Benni Mini
To Next Page
Loading...
