Komatsu 114E-3 Series, Руководство по ремонту, Страница: 272 / 342

SEN00458-01 40 Troubleshooting
14
114E-3 Series
S-7 Exhaust smoke is black (incomplete combustion) 1
*1: Code [559/CA559] and code [2249/CA2249] in E-mode
*2: Code [144/CA144] and code [145/CA145] in E-mode
General causes why exhaust smoke is black
q
Insufficient intake of air
q
Defective injection condition of fuel
q
Improper selection of fuel
q
There is overheating
See “S-14 Coolant temperature becomes too high (Over-
heating)“
q
Controller is controlling in derate mode
(limiting injection rate (output) because of an error in elec-
trical system)
Causes
Cl
ogg
ed ai
r cle
aner ele
m
ent
Se
ized
turboc
harger
, i
nterf
eren
ce of turboch
arger
De
fe
cti
ve cont
ac
t of
va
lve
an
d valve
se
at
Imp
rop
er va
lve
cl
earance
Lea
kage
of air betwe
en turb
ocha
rg
er
an
d cyli
nder hea
d
Crush
ed, c
log
ged
muf
fle
r
W
orn
p
iston ring
, cyl
ind
er
line
r
S
tuck, seize
d suppl
y pump pl
unge
r
Cl
ogg
ed, s
eize
d
inj
ector
Ab
nor
m
all
y w
or
n
in
ject
or
Imp
rop
er fuel
inj
ection
p
re
ssure
De
fe
cti
ve cool
ant temp
era
tu
re
se
nsor
, w
irin
g
h
arness
Questio
ns
Confirm recent repair history
Degree of use of machine
Operated for long period
E E E E
Exhaust smoke color
Suddenly became black
w w Q Q Q
Gradually became black
w Q Q
Blue under light load
w
Non-specified fuel is being used
Q Q
Oil must be added more frequently
w
Power was lost
Suddenly
w Q Q Q
Gradually
Q Q Q Q
Dust indicator is red (if indicator is installed)
w
Muffler is crushed
w
Air leaks between turbocharger and cylinder head, clamp is loosened
w
C
heck items
Engine is operated in low-temperature mode at normal temperature
Q Q
When exhaust manifold is touched immediately after starting engine, temperature of some
cylinders is low
Q w
When engine is cranked, interference sound is generated around turbocharger
w
When engine is cranked, abnormal sound is generated around cylinder head
w
Torque converter stall speed or pump relief speed is high (Fuel is injected excessively)
Q
Exhaust noise is abnormal
Q w Q
Engine does not pick up smoothly and combustion is irregular
Q Q Q Q Q w
Blow-by gas is excessive
w
If spill hose from injector is disconnected, abnormally much fuel spills
w
T
ro
ubl
esho
oti
ng
Inspect air cleaner directly
q
When turbocharger is rotated by hand, it is found to be heavy
q
When compression pressure is measured, it is found to be low
q q
Inspect valve clearance directly
q
When muffler is removed, exhaust sound improves
q
Carry out troubleshooting according to “No-pressure feed by supply pump (*1)” in E-mode
q q
When a cylinder is cut out for reduced cylinder mode operation, engine speed does not
change
q
Carry out troubleshooting according to “Abnormality in coolant temperature sensor (*2)” in
E-mode
q
Confirm with INSITE or with monitoring function on applicable machine side
q
Remedy
Cl
ea
n
Re
pl
ac
e
Re
pl
ac
e
Ad
ju
st
Correct
Re
pl
ac
e
Re
pl
ac
e
Re
pl
ac
e
Re
pl
ac
e
Re
pl
ac
e
Re
pl
ac
e
Re
pl
ac
e