Lesson 4/Learning Event 1
SUBASSEMBLIES OF THE LUBRICATION SYSTEM
Now let's examine the individual parts found in the lubrication system of an engine.
The reservoir for storing the oil is known as the oil pan. It is sometimes known as the crankcase cover because
it does seal the bottom of the engine crankcase.
Most oil pans, especially on military wheeled vehicles, have a fairly deep section known as the sump. The sump
serves several purposes.
First, it increases the amount of oil the oil pan can hold.
Second, it provides a pocket into which dirt, water, and metal particles can settle.
Third, it reduces the amount of sloshing back and forth that the oil can do.
Fourth, it houses the pickup screen for the oil pump and ensures the delivery of oil to the pump as
long as there is any in the oil pan.
Finally, the sump makes certain that oil will be available at the pickup screen when the vehicle is
climbing or going down steep grades.
If the oil pan is shallow and has a flat bottom, all of the oil will run to the front or rear of the oil pan when
the vehicle travels over steep grades. With the deep sump, part of the oil will always be present in the sump so
the oil pump can pick it up.
Some oil pans also have baffle plates which help to reduce the amount of sloshing the oil can do as the vehicle
travels over rough roads or cross-country. Excessive sloshing is undesirable because it tends to keep the dirt
and water mixed with the oil instead of letting them settle to the bottom of the sump.