Daedong DSC48, Workshop Manual

Page: 97 / 290

Apr. 2007
2
-21
DSC48
3. DISASSEMBLY AND SERVICE
3.1 TROUBLESHOOTING
Symptom Probable cause Solution
Engine does not start • No fuel
• Air in the fuel system
• Water in the fuel system
• Fuel pipe clogged
• Fuel
fi lter clogged
• Excessively high viscosity of fuel or engine oil
at low temperature
• Fuel with a low cetane number
• Fuel leak due to loose injection pipe nut
• Incorrect injection timing
• Excessively worn fuel camshaft
• Injection
nozzle clogged
• Malfunctioning injection pump
• Malfunctioning fuel pump
• Seizure of crankshaft, camshaft, piston, or
bearing
• Compression leak from cylinder
• Improper valve seating, valve spring broken,
valve seized
• Improper valve timing
• Excessively worn piston ring and liner
• Excessive valve clearance
Replenish fuel
Bleeding air
Clean fuel tank or change fuel in pipe
Clean
Clean or replace
Use the speci
fi ed fuel or engine oil
Use the speci fi ed fuel
Tighten nut
Adjust
Replace
Clean or replace
Repair or replace
Repair or replace
Repair or replace
Replace head gasket, tighten cylinder
head bolt, repair or replace glow plug
or nozzle holder
Repair or replace
Correct or replace timing gear
Replace
Adjust
Starter does not run • Battery discharged
• Malfunctioning
starter
• Malfunctioning starter switch
• Open
circuit
Charge
Repair or replace
Repair or replace
Connect
Engine revolution is
not smooth • Fuel fi lter clogged or dirty
• Air cleaner clogged
• Fuel leak due to loose injection pipe nut
• Malfunctioning injection pump
• Incorrect nozzle opening pressure
• Injection nozzle stuck or clogged
• Fuel
over fl ow pipe clogged
• Malfunctioning governor
Clean or replace
Clean or replace
Tighten nut
Repair or replace
Adjust
Repair or replace
Clean
Repair
Either white or blue
exhaust smoke is
observed • Excessive engine oil
• Excessively worn or stuck piston ring and liner
• Improper injection timing
• Insuf
fi cient compression
Reduce to the speci fi ed level
Repair or replace
Adjust
Adjust top clearance
Either black or dark
gray exhaust smoke
is observed • Overloaded
• Low grade fuel used
• Fuel
fi lter clogged
• Air cleaner clogged
Lessen load
Use the speci
fi ed fuel
Clean or replace
Clean or replace