Komatsu 114E-3 Series - S-7 Exhaust Smoke is Black (Incomplete Combustion)

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
Clogged air cleaner element Seized turbocharger, interference of turbocharger Defective contact of valve and valve seat Improper valve clearance Leakage of air between turbocharger and cylinder head Crushed, clogged muffler Worn piston ring, cylinder liner Stuck, seized supply pump plunger Clogged, seized injector Abnormally worn injector Improper fuel injection pressure Defective coolant temperature sensor, wiring harness
Questions
Confirm recent repair history
Degree of use of machine Operated for long period EE EE
Exhaust smoke color
Suddenly became black w w QQQ
Gradually became black wQQ
Blue under light load w
Non-specified fuel is being used QQ
Oil must be added more frequently w
Power was lost
Suddenly wQQQ
Gradually QQQQ
Dust indicator is red (if indicator is installed) w
Muffler is crushed w
Air leaks between turbocharger and cylinder head, clamp is loosened w
Check items
Engine is operated in low-temperature mode at normal temperature QQ
When exhaust manifold is touched immediately after starting engine, temperature of some
cylinders is low
Qw
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 QwQ
Engine does not pick up smoothly and combustion is irregular Q QQQ Qw
Blow-by gas is excessive w
If spill hose from injector is disconnected, abnormally much fuel spills w
Troubleshooting
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 qq
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 qq
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
Clean
Replace Replace
Adjust
Correct
Replace Replace Replace Replace Replace Replace Replace