PRIN. OF INTERNAL COMBUSTION ENGINES - OD1619 LESSON 2/TASK 2
FIGURE 55. OIL FILTERING MEDIUMS.
(a) The fullflow (figure 56, view A, on the following page) is the most
popular in current automotive design. All oil in a fullflow system is circulated
through the filter before it reaches the engine. When a fullflow system is used,
it is necessary to incorporate a bypass valve in the oil filter to allow the oil to
pass through the element in the event it becomes clogged. This will prevent the
oil supply from being cut off to the engine.
(b) The bypass system (figure 56, view B) diverts only a small quantity of the
oil each time it is circulated and returns it directly to the oil pan after it is
filtered. This type of system does not filter the oil before it is sent to the
(1) Purpose. Some automotive configurations do not allow sufficient airflow
around the crankcase to allow the oil to dissipate heat. Engines in heavy duty and
desert use must be able to dissipate more heat from their oil than normal airflow
can accomplish. An oil cooler is installed in all of these cases.