Yamaha YEP-321 Owners Manual - Page 14

Maintenance ● Body maintenance Use a polishing cloth to gently wipe the instrument's surface. If dirt or tarnish is obvious, the following products can be used. For lacquer finishes Polishing cloth + lacquer polish For silver plate Silver cloth + silver polish For a beautiful shine, buff the instrument with a silicone cloth. 2. Remove dirt from the inside of the valve cas- ings. * In models that are equipped with valve springs under the valves, remove the springs from the valve casing before cleaning. 3. Use the gauze to remove dirt from the pistons. The piston is the most important part of the instrument. Never treat the pistons roughly, drop the piston, or let the piston fall, etc. If the piston becomes damaged or dented, never return it to the valve casing. Contact the dealer from whom you purchased the instrument. ■ Once or Twice a Month Maintenance ● Piston and valve casing maintenance The pistons and valve casings are designed with very little clearance between each other therefore, it is very important that these precision parts be handled with care. 1. Wrap a cleaning rod with gauze so that no metal is exposed. Cleaning rod Gauze 4. After applying valve oil, gently return the pis- ton to its corresponding valve casing. At this time, make sure that the valve guide properly fits into the notch. After firmly tightening the valve cap, move the piston up and down a few times to distribute the oil evenly. * Exposed metal can damage the instrument. 30