See Figures 1 through 10
Three types of air cleaners have been used: the oil bath type, the dry cartridge type and the dry cartridge with polyurethane wrap type.
The 4-134, 6-226 and 6-230 engines should have the oil bath type cleaned and refilled every 2,000 miles. All other engines with oil bath units should have them cleaned every 6,000 miles. Under dusty conditions, the units should be checked every week or more frequently, if conditions warrant. To clean and refill an oil bath type, remove it from the engine, disengage the oil cup from the unit, empty the oil, clean out the dirt from the oil cup and wash the element thoroughly in a detergent solvent. Dry the element thoroughly in a detergent solvent. Dry the element with compressed air. In the summer, refill the cup with 40 or 50 weight engine oil. In the winter, use 20 weight.
Engines with the dry paper type filter should have the filter replaced every 12,000 miles. Under dusty conditions, the element should be checked weekly, or more often if conditions warrant and should be replaced at the first signs of clogging.
On engines using a dry paper filter with the polyurethane wrap, the wrap should be carefully removed every 6,000 miles. Shake the dirt from the wrap, do not wash it, squeeze the old oil out by pressing it flat between two rags, then liberally soak it with SAE 10W-30 engine oil. Squeeze it flat to remove excess oil. At the same time, direct compressed air at the inside of the paper element to remove dirt. Replace the paper element every 15,000 miles, or sooner if necessary.