1. Loosen the wing bolt and remove the air cleaner assembly from the air
inlet housing. The cleaner may then be separated into two sections; the
upper section or body assembly contains the filter element, the lower section
consists of the oil cup, removable inner cup or baffle and the center tube.
2. Soak the body assembly and element in fuel oil to loosen the dirt; then
flush the element with clean fuel oil and allowit to drain thoroughly.
3. Pour out the oil, separate the inner cup or baffle from the oil cup,
remove the sludge and wipe the baffle and outer cup clean.
Push a lint-free cloth through the center tube to remove dirt or oil.
5. Clean and check all of the gaskets and sealing surfaces to ensure air
6. Refill the oil cup to the oil level mark only, install the baffle, and
reassemble the air cleaner.
7. Check the air inlet housing before installing the air cleaner assembly on
the engine. The inlet will be dirty if air cleaner servicing has been neglected or
if dust-laden air has been leaking past the air cleaner or air inlet housing seals.
Fig. 8. Light-Duty Oil Bath Air Cleaner
Make sure that the air cleaner is seated properly on the inlet housing
and the seal is installed correctly.
Tighten the wing bolt until the air cleaner is securely
Service the heavy-duty oil bath air cleaner as
Loosen the wing nuts and detach the lower
portion of the air cleaner assembly.
2. Remove the detachable screen by loosening
the wing nuts and rotating the screen one-quarter
One of the most important steps in properly cleaning
the tray type oil bath air cleaner is a step that is
most overlooked. Unless the filter tray is thoroughly
cleaned, satisfactory performance of the engine
cannot be realized.
The presence of fibrous
material found in the air is often underestimated and
is the main cause of the malfunctioning of heavy-
duty air cleaners. This material comes from plants
and trees during their budding season and later from
airborne seed from the same sources. Figure 10
illustrates the severity of plugging in a tray that is
50% plugged. The solid black areas in the mesh are
accumulations of this fibrous material. When a tray
is plugged in this manner, washing in a solvent or
similar washing solution will not clean it
It must be blown out with high
pressure air or steam to remove the material that
Fig. 9. Heavy-Duty Oil Bath Air Cleaner
accumulates between the layers of screening.