Komatsu 114E-3 Series, Shop Manual

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40 Troubleshooting SEN00458-01
114E-3 Series
23
S-16 Vibration is excessive 1
General causes why vibration is excessive
q
Defective parts (abnormal wear, breakage)
q
Misalignment between engine and chassis
q
Abnormal combustion
a
If abnormal noise is made and vibration is excessive, carry out trou-
bleshooting for “S-15 Abnormal noise is made”, too.
Causes
S
tuck dynamic valve system
(valv
e
, rocker lever)
W
orn
mai
n b
earin
g, co
nnecting
ro
d
beari
ng
Improp
er
g
ear tra
in backla
sh
W
orn
camsha
ft
bushi
ng
Improp
er
fue
l inje
ctio
n ti
mi
ng (abn
orma
lity
in
coola
nt
tempe
ra
tu
re
se
nsor
, bo
ost tempera
ture
sen
sor)
L
oose
en
gin
e mo
unting
bo
lts,
broken
cu
sh
ion
s
Misa
lign
m
ent
b
etween
e
ngin
e and de
vices on app
licab
le machin
e si
de
Bro
ke
n output shaf
t, p
art
s in
d
amper on ap
plica
ble machin
e side
Questio
ns
Confirm recent repair history
Degree of use of machine Operated for long period
E E E
Condition of vibration
Suddenly increased
Q Q
Gradually increased
Q Q Q
Non-specified oil is being used
Q Q
Metal particles are found when oil filter is drained
w w
Metal particles are found when oil pan is drained
w w
Che
ck items
Oil pressure is low at low idle
Q Q
Vibration occurs at mid-range speed
Q Q
Vibration follows engine speed
Q Q Q Q
Exhaust smoke is black
w Q
T
roub
lesho
oting
Inspect dynamic valve system directly
q
Inspect main bearing and connecting rod bearing directly
q
Inspect gear train directly
q
Inspect camshaft bushing directly
q
Confirm with INSITE or with monitoring function on applicable machine side
q
Inspect engine mounting bolts and cushions directly
q
When alignment is checked, radial runout or facial runout is detected
q
Inspect output shaft or inside of damper directly
q
Remedy
Re
place
Re
place
Re
place
Re
place
Re
place
Re
place
Adjus
t
Re
place