Doosan DP158LDF - Failure Diagnosis

8. Fuel system
133
Failure Diagnosis
Governor Electric type
Fuel feed
pump
Type Mechanical type injection pump
Capacity
(L/hr)
630
Injection noz-
zle
Type Multi hole type
Opening pres-
sure (MPa)
28
Fuel filter Full flow, Cartridge type with water drain valve
Fuel Used Diesel fuel oil
Item
DP222L
Remarks
DP222LAS DP222LBS DP222LBF DP222LCS DP222LCF
Symptom Causes Troubleshooting
1.
Engi
ne does not start
A. Fuel is not supplied from
the fuel delivery pump
B.
Fuel
is not injected from
the fuel injection pump
C.
I
mproper fuel injection tim-
ing
D.
Fuel
injection nozzle not
working
• Clogged fuel pipe, or air entered the fuel pipe line
• Defective delivery pump valve
• Seized delivery pump piston or push rod
•Correct
• Replace
• Disassemble / correct
• Clogged fuel filter cartridge
• Air entered to the fuel filter or injection pump
• Seizure or defect in the plunger or delivery valve
• Clean / replace
•Bleed
• Disassemble / correct
• Defective installation of fuel injection pump bracket
• Defective adjustment of the fuel injection pum
p
t
appet
• Excessively worn cam of camshaft
• Inspect / correct
• Inspect / correct
• Replace
• Seizure of needle valve of nozzle
• Fuel leakage between nozzle and needle valve
• Improper fuel injection pressure
• Service or replace
• Service or replace
•Adjust
2.
Engi
ne starts but stop
s
immediately
• Clogged fuel filter or clogged pipe between fuel
delivery pump and injection pump
• Air entered into fuel
• Insufficient supply of oil by fuel delivery pump
• Clogged air breather in fuel tank, causing insuffi-
cient fuel supply.
• Clean or replace
• Air bleeding
• Disassemble / correct
• Replace breather
3.
I
nsufficient engine power
• Excessively work plunger
• Improper injection timing
• Defective delivery valve
• Excessive fuel leakage in injection nozzle
• Nozzle not working properly
• Replace
•Adjust
• Replace
• Service or replace
• Disassemble / correct
4.
Engi
ne knocking occurs
• Early injection timing
• High nozzle injection pressure
• Nozzle not working properly
•Adjust
•Adjust
• Disassemble / correct