TM 5-3895-383-24
9.
Misfiring cylinder(s):
Refer to Problem No. 4, Engine Misfiring Or
Running Rough.
10.
Intake/exhaust valves or piston rings leak compression.
11.
Defective fuel injector(s):
Defective fuel injectors will normally cause the
engine to "misfire" (injection not regular) and run
rough, but can cause too much smoke with the
engine running smooth. Remove and check the
fuel injectors. Use the 1U6661 Pop (Injector)
Tester to check the injectors for proper operation.
Refer
to
Special
Instruction,
SEHS8867
for
additional information.
Black Smoke
Probable Cause(s):
12.
Fuel injection timing Retarded:
Check and make necessary adjustments as per
Testing and Adjusting Section of this Service
Manual.
13.
Defective fuel injector(s):
Defective fuel injectors will normally cause the
engine to "misfire" (injection not regular) and run
rough, but can cause too much smoke with the
engine running smooth. Remove and check the
fuel injectors. Use the 1U6661 Pop (Injector)
Tester to check the injectors for proper operation.
Refer
to
Special
Instruction,
SEHS8867
for
additional information.
14.
FRC setting too rich:
15.
Inlet or exhaust air leakage or restriction:
16.
Defective Turbocharger:
Check inlet manifold for oil and repair turbocharger.
Blue Smoke
Probable Cause(s):
17.
Oil level in engine too high:
Do not put too much oil in the crankcase. If the oil
level in the crankcase goes up as the engine is
used, check for fuel in the lubrication oil. Refer to
Problem No. 34, Fuel In Lubrication Oil.
18.
Failure of turbocharger oil seal:
Check inlet manifold for oil and repair turbocharger.
19.
Worn valve guides:
See the Specifications Section of the Service
Manual for the maximum permissible wear of the
valve guides. If necessary, recondition the cylinder
head.
20.
Worn piston rings and/or cylinder walls:
Worn piston rings and/or cylinder walls can be the
cause of blue smoke and can cause a loss of
compression. This condition can cause more than
the normal amount of fumes (blow-by) coming from
the crankcase breather. The 8T2700 Indicator
Group is used to check the amount of blow-by. The
test
procedure
is
in
Special
Instruction,
SEHS87112.
If
necessary,
make
a
visual
inspection of the cylinder walls and piston rings.
Measure the cylinder walls and piston rings. For
the cylinder and piston ring specifications see the
Specification Section of the Service Manual.
Repair and replace pats as necessary.
NOTE:
High wear at low hours is normally caused by dirt
coming into the engine with the inlet air.
21.
Wear or damage to pistons:
Check piston ring to groove clearance. Pistons
which have worn grooves and pistons with damage
or defects can cause blue smoke and too much oil
consumption. Make sure the oil return holes under
the oil ring are open. Replace pistons as
necessary.
Problem 24: Engine Has Low Oil Pressure
Probable Cause(s):
Defect In Oil Pressure Gauge Or Sending Unit
Dirty Oil Filter Or Oil Cooler
Diesel Fuel In Lubrication Oil
Oil Pump Has A Defect
Oil Pump Suction Pipe Has A Defect
Oil Pressure Relief Valves Do Not Close
Too Much Clearance Between Rocker Arm Shaft
And Rocker Arms
Too Much Clearance Between Camshaft And
Camshaft Bearings
Too Much Clearance Between Crankshaft And
Crankshaft Bearings
1.
Defect in oil pressure gauge or sending unit:
Install new gauge or sending unit.
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