TM10-3930-660-20 18-22. BOOM HOSE PULLEY -   REPLACE  (Cont’d) Loosen nut (10) as needed during Step 9. 9. SEPARATE EXTEND CHAIN (11) FROM CLEVIS (12) TO CREATE WORK ROOM. a. Remove two retainer rings (13) and clevis pin (14) from clevis (12). b. Separate extend chain (11) from clevis  (12). Loosen hoses (3) and boom electrical cable (4) as required during removal of pulley  (15). 10. REMOVE BOOM  HOSE PULLEY (15). a. b. Remove two capscrews (16), two lockwashers (17), and two flatwashers   (18). Remove pulley support (19) and pulley  (15). 18-86