1) Verify that the valve bearing 'plates' have not become loose. The plates are the round disks under the valve caps, and also the plates on the other side of the valve casings that hold the bumpers for the linkage. These plates contain the bears that align the rotors in the valve casing. The plates should not move (or 'click') when gentle finger pressure is put on them. If the plates are loose it is probably best to take it to a repair shop to have the valves adjusted. The grinding noise could be caused by the rotor being out of alignment and rubbing on the valve casing.
2) If you have not been doing so... besides oiling under the valve caps, put several drops of light oil on other side of the rotor. Just drop the oil on the gap between the moving rotor arm and the fixed valve plate, work the valves and the oil will flow into the bearing. Jay Kosta Endwell NY amateur player, not repair tech.... _______________________________________________ post: horn@music.memphis.edu unsubscribe or set options at http://music2.memphis.edu/mailman/options/horn/archive%40jab.org
