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