TM 5-3895-382-24
5.
The piston rings are worn.
Replace the piston rings.
6.
The engine consistently runs below the normal
operating
temperature.
The
water
temperature
regulator is defective.
Replace the water temperature regulator.
Problem 19
The engine has low oil pressure.
Probable Cause
1.
The oil filter is restricted.
Install a new oil filter. Replace the lubricating oil in the
engine with clean oil. Check the operation of the
bypass valve for the filter.
2.
Fuel is in the lubricating oil.
Determine the source of the fuel. Refer to Problem 15.
3.
Too much clearance exists between the bore of the
rocker arm and the rocker shaft.
Check for adequate lubrication of the rocker arms.
Replace parts which are worn.
4.
The suction pipe for the oil pump is defective.
Replace the suction pipe.
5.
The engine oil bypass valve does not operate correctly.
Clean the bypass valve. Replace defective parts.
6.
The oil pump does not operate correctly.
The oil pump must be repaired or replaced.
7.
Too much clearance exists between the crankshaft and
the crankshaft bearings.
Replace the crankshaft or the crankshaft bearings.
8.
Too much clearance exists between the camshaft and
the camshaft bearings.
Replace the camshaft or the camshaft bearings.
Problem 20
The engine uses too much lubrication oil.
Probable Cause
1.
The engine contains too much lubrication oil.
Drain the excess oil from the oil pan.
2.
Oil lines have leaks.
Find the source of the oil leaks. Repair the line or fitting.
3.
The valve guides are worn.
Refer to Problem 18.
4.
The piston rings are worn.
Replace worn parts.
Problem 21
The engine coolant is too hot.
Probable Cause
1.
The air flow through the radiator is restricted.
Clean the exterior of the radiator in order to remove all
restrictions.
2.
The coolant level in the engine is low.
Add coolant into the radiator to the correct level.
3.
The pressure cap is defective.
Test the operation of the pressure cap. Replace a
defective pressure cap.
4.
Gases from combustion are in the coolant.
Find the source of the entry of the gases from
combustion into the coolant system. Repair the source
of the problem.
5.
The water temperature regulator is defective.
Test the water temperature regulator for correct
operation. Replace a defective water temperature
regulator.
6.
The water pump is defective.
The water pump must be repaired or replaced.
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