CARBURETOR
AIR CLEANER
VA LV E
COVER
CRANKCASE
TUBE
B R E AT H E R
AIR
V E N T I L ATO R
VA LV E
B R E AT H E R
I N TA K E
TUBE
MANIFOLD
Y
W-B
BLO
CRANKCASE
O I LL
OI
ASf05022
Figure 5-22.--Positive crankshaft ventilation.
using a new gasket, or just the gasket and cover on filter
foreign matter tends to stick to the sides of the oil pan
housings without drain plugs.
when the engine is cold. Usually, the filter elements
are changed at the time the oil is changed in the
On the type of filter that does not have a
crankcase. On new engines, the oil may be changed
replaceable element, disconnect the oil lines to the old
after running the engine for only a short period of
filter, dismount the filter, install the new one, and
time. This ensures that the engine is broken in with
reconnect the oil lines.
the cleanest oil possible and that all contaminates are
The screw-on type of filter, which is disposable,
removed during break-in, according to the
has an integral gasket. Installation instructions are
manufacturer's instructions or according to shop
printed right on the filter or included in the carton. The
policy. The filter element should be replaced with the
greatest danger with this filter is installing it too tight.
type recommended by the manufacturer. Be sure to
remove the old gasket and make sure that the new
After filling the oil pan with new oil, recheck the
gasket under the cover or in the crankcase is properly
oil level to be certain that the oil column reaches the
fitted.
FULL marking on the dipstick. Then, run the engine
for a few minutes to ensure no leaks exist, particularly
In replacing the filter element, remove the drain
around the oil filter housing and the oil drain plug. Get
plug from the bottom of the housing. Next, remove the
into the habit of looking at the ground or pavement over
cover by loosening the center bolt or clamp. Now lift
which a vehicle has been parked for any oil spots that
out the old element, and wipe the inside of the housing
may indicate leakage.
with a clean cloth. Some filter housings do not have
drain plugs. Therefore, you must first remove the
Ordinarily, low oil pressure readings may be due to
cover. Next, remove the filter element and take out the
thin or diluted oil, excessive heating, an improper
dirty oil with a siphon gun, and then wipe the inside of
grade of oil, or a low oil level in the oil pan. If no
the housing with a clean lint free cloth. Remove all
pressure shows, or if the pressure is erratic even after
traces of dirt or lint that remain inside. Install the new
replacing the old oil with new of the proper grade, a
element. Finally, replace the drain plug and the cover,
defective oil gauge may be the cause. If so, it is usually
5-22
