Nuts

When tightening a slotted or castellated nut, never slacken it in order to insert the split pin or locking wire, but tighten it to align the next slot. The exception is in those recommended cases where slackening the nut forms part of an adjustment e.g. bearing end float or preload adjustment. It difficulty is experienced, alternative washers or nuts should be selected, or a washer of a different thickness used. Where self-locking nuts have been removed, replace them with new ones.