TM 5-3895-383-24
Lubrication System
One of the problems in the list that follows will generally be an
indication of a problem in the lubrication system for the engine.
Too Much Oil Consumption
Oil Pressure Is Low
Oil Pressure Is High
Too Much Bearing Wear
Increased Oil Temperature
Too Much Oil Consumption
Oil Leakage On Outside Of Engine
Check for leakage at the seals at each end of the crankshaft.
Look for leakage at the oil pan gasket and all lubrication
system connections. Check to see if oil comes out of the
crankcase breather. This can be caused by combustion gas
leakage around the pistons. A dirty crankcase breather will
cause high pressure in the crankcase, and this will cause
gasket and seal leakage.
Oil Leakage Into Combustion Area Of Cylinders
Oil leakage into the combustion area of the cylinders can be
the cause of blue smoke. There are four possible ways for oil
leakage into the combustion area of the cylinders:
1.
Oil leakage between worn valve guides and valve
stems.
2.
Worn or damaged piston rings, or dirty oil return holes in
the piston.
3.
Worn or damaged and/or intermediate ring not installed
correctly.
4.
Oil leakage past the seal ring in the impeller end of the
turbocharger shaft.
Too much oil consumption can also be the result if oil with the
wrong viscosity is used. Oil with a thin viscosity can be caused
by fuel leakage into the crankcase, or by increased engine
temperature.
Measuring Engine Oil Pressure
Tools Needed
1U5470
Engine Pressure Group
1
8J7844
Adapter (3/4-16 to 1/4 NPTF)
1
3K0360
O-ring Seal
1
Reducing Busing (14 NPTF to 1/8 NPTF),
4M5317
or 5P2720 Self-Sealing Probe Adapter with
1
5P2718 Pressure Probe
An oil pressure gauge that has a defect can give an indication
of low or high oil pressure.
1U5470 Engine Pressure Group
The 1U5470 Engine Pressure Group can be used to measure
the pressure in the system. This tool group has a gauge to
read pressure in the oil manifold. Special Instruction,
SEHS8524 is with the tool group and gives instructions for its
use.
6-80
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