MTU 12 V 4000 M23F Operating Instructions Manual page 93

Engine speed not steady
Cause
Fuel injection: Injector faulty
Speed transmitter defective
Engine governor defective
Charge-air temperature too high
Cause
Incorrect coolant concentration
Intercooler dirty
Engine room: Air-intake
temperature too high
Charge-air pressure too low
Cause
Air supply: Air filter clogged
Intercooler dirty
Exhaust turbocharger defective
Coolant leaks at intercooler
Cause
Intercooler leaky, major coolant
discharge
Black exhaust gas
Cause
Air supply: Air filter clogged
Fuel injection: Injector faulty
Engine: Overload
Blue exhaust gas
Cause
Too much oil in engine
Oil separator or oil-preseparator
of crankcase breather clogged
Exhaust turbocharger, cylinder
head, piston rings, cylinder liner
defective
Corrective action
u Replace (→ Page 179).
u Contact Service.
u Contact Service.
Corrective action
u Check (MTU test kit).
u Contact Service.
u Check fans and air supply/ventilation ducts.
Corrective action
u Check signal ring position of service indicator (→ Page 216).
u Contact Service.
u Contact Service.
Corrective action
u Contact Service.
Corrective action
u Check signal ring position of service indicator (→ Page 216).
u Replace (→ Page 179).
u Contact Service.
Corrective action
u Drain engine oil (→ Page 219).
u Replace.
u Contact Service.
MS150068/01E 2014-01 | Troubleshooting | 93