EE WAS USING A 3'BAR TO LOOSEN A SILO VALVE. THIS VALVE HAD BEEN INCORRECTLY TIGHTENED AND EE STRAINED HIS LT. SHOULDER WHILE PULLING ON BAR TO LOOSEN THE NUTS. EE REPORTED INJURY ON 10/4/0 2 BUT DID NOT REQUEST MEDICAL ATTENTION UNTIL 11/14/02 AND AT THAT TIME WAS PUT IN WORK HARDENING PROGRAM WITH RESTRICTIONS.