Doosan D35S-5 Service Manual page 149

Troubles
Idle is improper or idle
speed is unstable or
irregular
Exhaust gas (Black,
blue, white)
Engine lacks power,
acceleration is delayed
(Speedometer is normal,
no clutch slip)
D439E Service Manual
Possible causes
Loose fuel hose connection between
filter and supply pump
Air in the fuel system
Fuel filter is clogged. Or fuel supply is
no good because fuel line or injection
pipe leaks, pinched or pressed.
Poor injection
Improper injection timing
Mechanical defect of engine
Defective supply pump
Engine defect at high gear range
Engine temperature stays below
engine operation temperature.
Abnormal at max RPM
Defective Injection nozzle
Improper injection timing
Exhaust system malfunction
Mechanical defect of the engine
Defective supply pump
Non-input of QR code value
Accel pedal malfunction
Defective max. rpm
Air cleaner element polluted
Fuel filter is clogged. Or fuel supply is
no good because fuel line or injection
pipe leaks, pinched or pressed. Or fuel
filter leaks
Air in the fuel system
Defective injector nozzle
Improper injection timing
Mechanical defect of engine
Defective supply pump
Tighten or repair.
Air bleeding of fuel system
Check hose or fuel line. Replace fuel
filter.
Check, replace injector.
Check ECU.
Compression test, repair engine.
Let the engine at idle after replacing
pump.
Observe appropriate shift speed.
Check rail pressure and cooling
system.
Replace thermostat.
Check and replace supply pump.
Check and repair or replace.
Check ECU.
Check if deformed or clogged.
Compression test, repair engine.
Replace pump.
Check the input of QR code value.
Check if it matches the QR value on
the injector.
- Check the history of trouble codes,
check rail pressure. (Target value,
Actual value)
- Input the improved ECU data
Check and replace supply pump
Clean or replace.
Check fuel line and hose, replace fuel
filter.
Air bleeding of fuel system
Check, repair or replace.
Check ECU.
Compression test, repair engine.
Check after replacing pump.
147
Corrective actions
4. Fuel system