Geely Diagnosis Flow. Manual part — 65

257

No. 184 Buzzing noise at rear wheel while driving at high speed

Malfunction

Causes

Solution

Bearings of two rear wheels worn, damaged

Check bearings of two rear wheels are worn, damaged;
if so, replace;

Positioning misadjustment of rear wheel

Check positioning of rear wheel is misadjusted; if so,
make positioning adjustment;

Buzzing noise at
rear wheel while
driving at high
speed

Pressure of two rear wheels normal

Check pressure of two rear wheels is normal; if
abnormal, adjust it to standard value;

Buzzing noise at rear wheel while driving at high speed

Replace

Bearings of two rear wheels worn, damaged

Positioning misadjustment of rear

wheel

Positioning
adjustment

Adjust

Pressure of two rear wheels normal

Abnormal

Normal

Abnormal

Abnormal

Normal

258

No. 185 Braking force of brake master cylinder insufficient

Malfunction

Causes

Solution

Gas within brake pipe

Check if the air exists; empty the air at exhaust hole of
wheel cylinder;

Brake pipe with leakage

Check if leakage occurs, usually at connections;
properly increase torque.

Brake master cylinder valve with poor sealing

After uses for a certain time, due to increase of foreign
substances within brake liquid and abrasion of valve,
sealing of valve becomes poor; thus replace the valve.

Main leather ring of brake master cylinder worn

After long-time uses and abrasion with cylinder body,
main leather ring of brake master cylinder is worn; thus
replace main leather cup;

Brake pedal with
too long stroke;
when stepping on
the pedal, no
obvious braking
effect, with braking
distance larger
than standard

Brake master cylinder body ragged

Due to long-time uses and sanitation within the vehicle,
brake master cylinder body is filled with hard
substances such as sandstone. During working, inner
wall of cylinder body is ragged, causing poor sealing
with leather ring, and internal leakage; replace brake
master cylinder.

Braking force
insufficient

Pipe with leakage

Eliminate leakage

Brake master cylinder valve with poor
sealing

Replace valve

Main leather ring of brake
master cylinder worn

Replace main leather
ring

Main leather ring of brake
master cylinder worn

Replace main leather
ring

Inner wall of brake master
cylinder body ragged

Replace brake master
cylinder

Leakage

No

Poor sealing

Worn

Worn

Ragged

No

No

Poor

259

No. 186 Stepping on pedal too heavily

Malfunction

Causes

Solution

(1) Vacuum connecting hose leaking;

As near to the engine, rubber hose is increasingly aged
due to its high temperature, easily causing cracks,
leaking vacuum, and reducing degree of vacuum of
vacuum booster, making function of booster ineffective.

(2) Non-return valve of booster ineffective;

As non-return valve of booster is the valve from the
engine to booster, if non-return valve is ineffective, then
vacuum chamber of the booster is equal to vacuum
source pressure, when the engine is with low revolution,
degree of vacuum will be insufficient, and causing
booster semi-effective.

(3) Leakage at connection of brake master
cylinder

Connection between booster and brake master cylinder
is one important sealing point of booster, as O-ring
sealing. After uses for long time, O-ring is aging, with
reducing sealing performance, causing function of
booster ineffective.

Stepping on pedal
too heavily, with
ineffective or
semi-ineffective
booster function

(4) Leakage of booster assembly;

As the booster has generally rubber sealing parts
inside, leakage will easily occur, causing function of
booster ineffective.

Stepping on pedal too heavily

Vacuum connecting hose leaking

Eliminate leakage

Non-return valve of booster
ineffective

Replace non-return
valve

Leakage at connection of brake master
cylinder

Replace O ring

Leakage of booster
assembly

Replace booster

Air leakage

No

Air leakage

Ineffective

Leaking

No

No

260

No. 187 Common malfunction diagnosis and Solution for Geely

automobile tire

Serial
No.

Malfunction

symptom

Causes

Prevention

1

Bar blows up

Tire tread torn, blown
up

1. After the tire crown is damaged by sharp articles, the
steel wire is rusty and snapped off, with reduced
strength.
And under impact of outside force, it is blown up; also
blown up under strong impact during driving at high
speed.

Drive on favorable
road or drive at low
speed

2

Tire tread
deformed

Steel wire of bracing
ply of tire tread rusty,
and tire casing
deformed.

Steel wire of bracing ply damaged by sharp articles on
the road, causing rusty and deformed tire casing.

Avoid sharp articles

3

Bar cracked

Tire sidewall bulges
out under charging
status, and
corresponding inner
cord thread broken.

Cord thread broken as tire is under strong impact of road
barriers, etc. causing low power at this point, and the
surface is bulging out.

Avoid barriers or
drive at low speed

4

Cut through
(repair)

Tire is cut through
from outside, and
with repair marks

Tire stabbed by sharp articles on the road; repairs
needed.

Avoid sharp articles

5

Pattern
bruising

Tire crown rubber
and casing torn, and
fallen out

Tire stabbed by sharp articles on the road, and rubbing
with the road surface if continue driving.

Drive on favorable
road or drive at low
speed

6

Spongy
surface of
the pattern

Tire crown rubber as
in soybean curd
residue type, and
rubber is squeezed
with broken stone
inside

Tire is running under low temperature in winter. As
temperature is too low, rubber’s performance is reduced,
and also squeezed with broken stone on the road,
causing cracks of rubber.

Replace winter tire

7

Tire sidewall
stabbed or
cut through

Racially cracked,
cord thread broken,
or even blown up if
severe with bruising
marks.

Tire stabbed (cut through) by sharp articles.

Drive on favorable
road and avoid
sharp articles

8

Rubber
chapped

Rubber surface with
turtleback cracks.

With being placed for long time under charging status,
ultraviolet radiation, erosion by ozone and heat, rubber
surface of the tire is cracked, but tire structure is not
damaged, which could be used later.

Avoid direct sun
shining, ozone,
heat source

10

Tire bead
cracked

Rubber between tire
bead and sidewall
cracked, and cord
thread broken.

Driving under lower pressure, excess flections caused by
frequent steering, braking with a rush, it causes cracks
with fatigue.

Keep standard
pressure inside the
tire, and have good
driving habits