TM10-3950-672-24-2
Diagnosing Lubricating System
Malfunctions
Be sure to check items related to oil pressure, such as:
gauges, high and low oil level, excessive oil
High Oil Pressure
High oil pressure usually occurs after the engine is first
started in cold weather. The lubrication system does not
have a cold start relief valve. The pressure regulating
valve components are machined to a size that will
relieve the excessive pressure created by cold engine
oil.
Oil Pressure Regulating Valve
The engine will have high oil pressure if the regulator
sticks in the closed position. Check the regulator for
freedom of movement.
Low Oil Pressure
Low oil pressure can be caused by several lubrication
system related malfunctions. To begin the investigation,
determine the engine operating conditions when the low
pressure was first observed.
Oil Level
Low oil level can cause low oil pressure.
Caution
Never operate the engine with the oil
level below the low (L) mark.
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