3-16. LUBRICATING OIL FILTERS - MAINTENANCE INSTRUCTIONS.
The full-flow dual type lubricating oil filter is installed ahead of the oil cooler in the lubrication system.
b. The filter assembly consists of a replaceable element enclosed within a shell which is mounted on an
adaptor or base. When the filter shell is in place, the element is restrained from movement by a coil spring.
c. All oil supplied to the engine passes through the filter before reaching the various moving parts of the
engine. Pump pressure forces the oil through a passage in the filter adaptor or base to the space surrounding
the filter element. The filtered oil is forced through the element to a central passage surrounding the center
stud and out through another passage in the filter adaptor or base and then to the oil cooler.
d. A valve, opening at approximately 18-21 psi (124-145 kpa), is located in the filter adaptor, or, on a
remote mounted filter, in the filter junction. This will by-pass the oil directly to the oil cooler should the filter
e. With the use of detergent lubricating oils, the color of the lubricant has lost value as an indicator of oil
cleanliness or proper filter action. Due to the ability of the detergent compounds to hold minute carbon
particles in suspension, heavy duty oils will always appear dark colored on the oil level dipstick.
f. Heavy sludge deposits on the filter elements at the time of an oil change indicates that the detergency
of the oil has been exhausted, and the oil drain interval should be shortened. The removal of abrasive dust,
metal particles and carbon must be ensured by replacement of the oil filter elements at the time the engine oil