TM5-4220-231-14&P 4-11.   Depth  Gage  Isolation   Valve  (DACC). This task covers:    Replace INITIAL   SETUP Tools Equipment Conditions General     Mechanics Tool   Kit Remove front   cover from    DACC   case (Para. 3-15 1-2) O-ring Installation and Removal Tool Remove rear    DACC   panel (Para. 3-15 3) Materials/Parts References Depth Gage Isolation Valve; Para. 4-2,    General Red, 13229E4597-2 Green, 13229E4597-3 Yellow, 13229E4597-4 O-ring, M83248/2-010 (2) O-ring, M8324812-904 (1) Nonionic Detergent Solution (NID)  GP (item    17,   Appendix D) a. Remove (1) Determine which depth gage isola- tion   valve is  to  be    replaced. These instructions are applicable to   any    of the three isolation valves, as    the configurations are   the   same. DEPTH GAGE ISOLATION VALVE (2) Remove the    tube (5)   from   valve (4) 5 by   positioning a   wrench on   union    nut 6,7 (6)   and one    on   the   valve body    (4). Turn union nut    counterclockwise. Remove, cut   and    discard O-ring    (7). 6,7 DEPTH  GAGE 4 4-34 Change 1