This ball bearing supports a rotating shaft within the cleaning system of a grain harvester. It is a single-row, deep-groove bearing with contact seals on both sides, which retain lubricant and exclude fine dust and chaff. The bearing is pressed into its housing and carries the radial and axial loads from the sieve-drive or fan shaft it supports. A worn bearing produces a rough, audible rumble during operation and can cause the driven component to wobble, leading to misalignment of the cleaning fan or sieve drive. The manufacturer machines the bearing races to the same internal clearance as the original assembly, so the shaft rotates freely without preload under normal operating temperatures. When replacing, press the bearing onto the shaft using the inner race only; pressing on the outer race can damage the seals or rolling elements.