Abstract: A dust collector based on filtration of dirty air in which the periodic backflushing of filtration elements is done by admitting atmospheric air at the filtration element exit port. The air is sucked backwards through the filtration element by the dust collector exit blower. Switching between normal usage and backflush is done by inserting a diverter valve containing a valve chamber between the filtration element discharge part and the clean air chamber. The porting of this valve chamber may be to either the atmosphere or to the clean air chamber, which being determined by twisting a shaft slightly less than 90 degrees, said shaft having valve closure plates attached to it at slightly greater than 90.degree. to each other. Twisting force need not be applied during normal operation nor to close off the atmospheric air port. Further, dust shields are provided around each filtration element to prevent backflushed dust moving directly to an adjacent filtration element.

Abstract: A method of reducing fuel and oil consumption in an internal combustion engine in which the cylinder walls of the engine are peened with glass spheres having a diameter within the range of form about 0.002 inches to about 0.004 inches. The glass spheres form a multiplicity of local depressions and surface compression at the points of impact and are directed against the cylinder walls for a period of time sufficient to form the depressions over the entire surface area without leaving flat portions of the surface between the depressions. In some embodiments the cylinder walls are coated with a lubricating agent such as graphite prior to being peened. After the peening step the walls are lightly honed to produce substantially flat supporting areas between the individual depressions.