TM  10-3930-643-34 HYDRAULIC  SYSTEM  TROUBLESHOOTING  AND  MAINTENANCE.  (cont) 12-7. Boom Assembly Valve. (Sheet 3 of 6) DISASSEMBLY  (cont) 9. Using a scribe, remove preformed packing (17) from plug (19). Discard preformed  packing  (17). 10. Remove items 20 thru 25 as an assembly and spring (18) from plug (19). 11. Using an 11/16” box and open end wrench, remove nut (20) and items 21 thru 23 as an assembly from poppet (25). 12. Using a scribe, remove preformed packing (21) and ring (22) from spacer (23). Discard preformed packing (21). 13. Remove preformed packing (24) from poppet (25). Discard preformed packing (24). Go to sheet 4 12-52