JAC Trucks. Manual — part 109

74

Trouble symptom and probable cause

Checking and remedy

(1) Hard steering, steering wheel doesn't return well

a. Insufficient lubrication of steering linkage mechanism
b. Improper alignment of front wheel
c. Improper toe in of front wheel
d. Improper camber and caster of king pin

e. Worn thrust bearing
f. Insufficient pressure of tire

(2) Abnormal worn tire

a. Improper position fix of front wheel
b. Improper pressure of front tire

a. Apply lubrication on king pin and ball stud
b. Adjust
c. Adjust
d. Check the linear for wear, and check knuckle and tie
rod for deviation, replace if necessary
e. Replace
f. Inflate properly

a. Adjust, and replace if necessary
b. Adjust, and inflate

5尧Front axle trouble shooting

HFC1048

series trucks

75

Trouble symptom and probable cause

Checking and remedy

渊3冤Vibrate oscillate

a. Improper position fix of front wheel

b. Worn king pin linear
c. Improper pretightening of hub bearing
d. Worn hub bearing
e. Loosen ball stud of tie rod
f. Loosen nuts on U-type bolt
g. Loosen hub nuts
h. Distorted wheel
i. Unbalance wheel
j. Wheel deviation
k. Asymmetry or insufficient inflation of tire

渊a冤front wheel location is wrong
渊b冤damage of the main bush
渊c冤the tight of wheel hub is wrong
渊d冤damage of wheel hub axle

a. Adjust, and replace if necessary
b. Replace linear
c. Adjust
d. Replace
e. Replace all end parts of tie rod
f. Tighten
g. Tighten
h. Replace
i. Adjust and balance
j. Adjust
k. Adjust, inflate

渊b冤replace
渊c冤adjust
渊d冤replace

76

Trouble symptom and probable cause

Checking and remedy

渊e冤cross pull rod ball end is loosen
渊f冤U type of nut and blot are loosen
渊g冤the nut of wheel hub are loosen
渊h冤the distortion of wheel
渊i冤the wheel are not imbalance
渊j冤the wap of wheel
渊k冤shortage of the air pressure

渊4冤leak grease from wheel hub
渊a冤damage of oil seal
渊b冤hub cover is loosen
渊c冤too much grease

渊e冤change the parts
渊f冤tighten
渊g冤tighten
渊h冤replace
渊i冤adjust the balance
渊j冤adjust
渊k冤adjust袁charge air

渊a冤replace
渊b冤tighten
渊c冤use grease to fix

HFC1048

series trucks

77

Trouble symptom and probable cause

Checking and remedy

(1) Abnormal noise from rear axle

a. Worn or damaged pinion bearing
b. Worn or damaged side bearing of differential
c. Loosen pinion bearing
d. Loosen differential bearing
e. Worn pinion and ring gear
f. Worn thrust washer
g. Worn differential spider
h. Worn pinion and ring gear
i. Worn or damaged side gear and planetary gear
j. Loosen tightening bolts of ring gear
k. Improper contact between ring gear and pinion
l. Worn pinion spline
m. Worn rear half shaft spline
n. Loosen hub bearing
o. Worn hub bearing

a. Replace bearing
b. Replace bearing
c. Adjust preload
d. Adjust preload
e. Adjust tooth space
f. Replace
g. Replace
h. Replace
i. Replace
j. Tighten
k. Replace or adjust
l. Replace
m. Replace
n. Replace
o. Adjust bearing preload

6. Rear axle trouble shooting

78

Trouble symptom and probable cause

Checking and remedy

(3) Hot rear axle

a. Oil leak because of damaged seal gasket, loosen oil

drain plug, and jammed vent hole, result in insufficient lu鄄
brication

b. Bad lubrication

c. Tight over between pinion and driven gear, tight over

on bearing

a. Fill up and readjust

b. Replace lubrication accord the season
c. Readjust

p. Loose tightening bolts of differential case
q. Insufficient oil
r. Bad oil

p. Tighten
q. Fill up
r. Replace

(2) half shaft seal Leaking

a. Jammed rear axle vent hole
b. Bad lubrication

c. Tight between pinion and driven gear, tight bearing,

and tight over on bearing

a. Fill up and readjust
b. Replace lubrication accord the season
c. Readjust

HFC1048

series trucks

79

Trouble symptom and probable cause

Checking and remedy

(2) Shake of steering wheel, instable steering

a. Loosen steering linkage mechanism
b. Unbalance front wheel
c. Pendulate too much
d. Damaged grinding wheel

e. Heavy wear or too big clearance of steering linkage

mechanism

a. Tighten properly
b. Balance the wheel
c. Adjust
d. Replace
e. Replace parts

(1) Hard to steer and steering wheel with bad return

a. Distorted main shaft, sliding shaft or column
b. Loosen universal joint or column cover
c. Improper rotation of steering wheel bearing
d. Insufficient lubrication of steering linkage mechanism
e. Low pressure tire

a. Replace parts
b. Replace universal joint
c. Replace parts
d. Fill up lubrication

e. Inflate properly

7. Steering mechanism trouble shooting

80

Trouble symptom and probable cause

Checking and remedy

(5) Heavy steering

a. Bad steering gear
b. Bad steering gear
c. Improper preload sector gear bearing

a. Replace piston set
b. Check pump for output pressure, replace if necessary
c. Adjust the pretightening force of bearing

(3) Wander front wheel

a. One of front brake or damper is disabled
b. One of front tire low pressure
c. Disalign or break of front leaf spring
d. Damaged grinding wheel
e. Improper toe in of front wheel

a. Adjust the brake clearance or replace damper
b. Inflate tires
c. Check front spring assembly
d.Adjust or replace
e. Readjust

(4) Power steering bump leaking

a. Damaged oil seal or O ring
b. Damaged oil seal locking nuts or oil-drain plug

a. Replace
b. Repair

HFC1048

series trucks

81

Trouble symptom and probable cause

Checking and remedy

渊2冤brake moment is partial

渊a冤brake shoe plate unseemliness
渊b冤one side of brake shoe plate is rustiness
渊c冤shoe plate have oil dirt
渊d冤the wheel is empty.
渊e冤brake drum is change

渊a冤adjust
渊b冤grease
渊c冤clean
渊d冤ordain air press
渊e冤adjust and grind

(1)shortage of brake

渊a冤adjust the brake room
渊b冤have some dirty things
渊c冤brake cam and shoe brake are rustiness
渊d冤brake room epithelia and pipe are leak air
渊e冤brake valve lead air

渊f冤the distance between brake and shoe plate is too large

渊g冤brake drum
渊h冤have dirty things on the pipe
渊i冤enter air to brake valve is slowly

渊a冤adjust the pull rod
渊b冤use buck to washing
渊c冤clean the rustiness and grease
渊d冤change epithelia ,check the air part
渊e冤change valve base
渊f冤adjust
渊g冤adjust and change
渊h冤clean it
渊i冤check enter air of the karat

8. Running brake trouble shooting