Figure 8-6. Oil Pickup and Strainer
filter is mounted outside of the engine and is designed to
the two most popular automotive filter mediums. They
be replaceable readily.
are held in place by sandwiching them between two
perforated metal sheets.
b. Filter Configurations (Fig. 8-7). There are two
basic filter element configurations: the cartridge type and
(2) Some heavy-duty applications use layers of
the sealed can type.
metal that are thinly spaced apart. Foreign matter is
strained out as the oil passes between the metal layers.
(1) The cartridge-type filter element fits into a
permanent metal container.
Oil is pumped under
d. Filter System Configurations. There are two filter
pressure into the container, where it passes from the
system configurations. These are the full-flow system
outside of the filter element to the center. From here the
and the bypass system. Operation of each system is as
oil exits the container. The element is changed easily by
removing the cover from the container when this type of
filter is used.
(1) The full-flow system (A, fig. 8-9) is the most
popular in current automotive design. All oil in a full-flow
The sealed can-type filter element is
system is circulated through the filter before it reaches
completely self-contained, consisting of an integral metal
the engine. When a full-flow system is used, it is
container and filter element. Oil is pumped into the
necessary to incorporate a bypass valve In the oil filter to
container on the outside of the filter element. The oil
allow the oil to circulate through the system without
then passes through the filter medium to the center of the
passing through the element in the event that it becomes
element, where it exits the container. This type of filter is
clogged. This will prevent the oil supply from being cut
screwed onto its base and Is removed by spinning it off.
off to the engine.
c. Filter Medium Materials (Fig. 8-8).
(2) The bypass system (B. fig. 8-9) diverts
only a small quantity of the oil each time it is
(1) Cotton waste or resin-treated paper are