Table 5-4. Troubleshooting - Continued
TROUBLE
PROBABLE CAUSE
REMEDY
4. Engine overheats
1. Lack of cooling air
1. Clean cooling air inlet
If cooling air
inlet is clean, refer to probable cause 2.
2. Excessive oil in crankcase
2. Refer to Table 5-3, drain oil to normal
level. If oil level is correct, refer to
probable cause 3.
3. Improper injector nozzle/s spray
3. Refer to INSPECTION AND PRE-
VENTIVE MAINTENANCE (Section
V) and replace injector nozzle/s. If
nozzle/s is/are not at fault, refer to
probable cause 4.
4. Timing of fuel injection pump
4. Refer to REPAIR (Section V). Check
incorrect.
and reset pump timing if necessary
If pump timing is correct, proceed to
probable cause 5.
5. Loose, worm, or damaged engine
5. Refer to REPAIR (Section V), disas-
components causing excessive
semble engine assembly. Replace
friction
parts which are worn.
5. Engine looses power. (Engine
1. Lack of combustion air
1. Refer to trouble number 3, probable
rpm [r/min] drops under load)
causes and remedies 1 and 2. If lack
of combustion air is not at fault, pro-
ceed to probable cause 2.
2. Tappet clearance incorrect
2. Refer to trouble number 3, probable
cause and remedy 3
If tappet clearance
is correct, refer to probable cause 3.
3. Cylinder head attaching nuts not
3. Check and tighten nuts to correct
tightened to correct torque value.
torque value if necessary. If nuts are
correctly tightened, refer to probable
cause 4.
4. Defective cylinder head gasket
4. Remove and inspect cylinder head
gasket. Replace a defective gasket. If
gasket is not defective, refer to probable
cause 5.
5. Valves sticking or not seating
5. Disassemble cylinder head. Check
correctly or piston rings worn
cylinder head parts and replace or
(compression not up to specifi-
repair parts that show damage or
cations.)
excessive wear Reassemble cylin-
der head
6
Air in fuel system
6. Check and tighten any loose fuel line
hardware, and replace damaged sealing
washers.
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