An air compressor that employs splash lubrication to lubricate and cool a piston kit that includes a cylinder and a piston reciprocating in the cylinder. In one form, cooling channels can be coupled to or formed on the cylinder to direct the lubricant that is splashed onto the cylinder to drain in a desired manner, such as helically around the exterior of the cylinder, to more effectively cool the piston kit. In another form, the cylinder can include an annular flange that can be bigger in diameter than a remainder of the cylinder. The annular flange can be received into a counterbore in a cylinder block. A cylinder head, which can be fastened to the cylinder block, can apply a clamping force to the annular flange to clamp or fix the cylinder to cylinder.