If the manual oiler works, both check valves are working as they should. If the gasket is correct and the impulse passage is open, the only thing that could keep the automatic oiler from working was if the piston doesn't go up & down with the impulse pressure. You may have to take it apart again and make sure there isn't something else stuck in there somewhere that it shouldn't be that is preventing the piston from stroking properly.
Mark
Mark