The nut on a Fender Jazz bass, or any bass, is one of the most basic parts. The nut on your Fender Jazz bass is even easier to replace than the strings. Despite the simplicity of the nut, having a worn nut on your bass can have a detrimental effect on the sound of your bass because the nut is partially responsible for maintaining the proper distance of your strings from the neck of the bass. When the nut on your Fender Jazz bass wears thin, you can replace it in minutes to keep your bass playing smooth.
Place your bass guitar on a flat, steady surface. Remove the strings of your bass for this process or loosen them and pull them off to the sides of the bass neck. Slip a flat screwdriver or butter knife between the upper flat side of the neck and the back of the nut. Gently pull the screwdriver back toward the neck to lift the nut away from its seating. If the nut has been painted over, it may be necessary to scrape the paint away with the end of the screwdriver before inserting it.
Clean up any excess dried glue from the nut seating. You can use light sandpaper or even the edge of your screwdriver. Once the glue is removed, stop sanding. You don't want to alter the depth of the seating.
Position the new nut the same way the old nut was positioned when you removed it. Place white wood glue along the bottom---or seated edge---of the nut and apply a light amount of glue over the seating area.
Line up the new nut and press it lower it to the nut seating on the bass neck. Press firmly to ensure the nut takes hold; then use a small cloth to wipe away any glue that seeps out around the edges.
Allow the nut to dry for three or more hours before you put the strings back on your bass.