TM 5-3895-374-24-2 SECTION VI Disassembly/Assembly Instructions Refer to Section VII for Sectional Drawings. -Preparation For Disassembly: SIHI’s ZTN Pumps are of the back pull-out design.  It is not necessary to remove the casing (2) from the system. 1. Lock out power supply to motor. 2. Close  isolating  valves  in  suction  and  discharge lines. 3. Allow liquid to cool. 4. Disconnect coupling. Refer to coupling manufacturer’s instructions. 5. Remove motor from baseplate.  Not necessary if spacer type coupling is used. 6. Be prepared to catch all the liquid that is trapped inside  the  pump  and  in  the  piping  between  the closed valves.  There are NO drain connections in the pump casing. B - Disassembly 1. Remove foundation bolts in the support foot (40) and bolts (170). 2. Remove rotating element  complete  with  bearing housing (210) and cover (3). 3. Remove    impeller    nut    (286)    and    lockwasher (292), impeller (30) and key (256). 4. Remove cover (3) complete with sleeve bearing (241). 5. Remove bolts (163) and bearing cover (221). 6. Press  shaft  (200)  complete  with  bearing  (230) out through the bearing housing. 7. Remove retaining ring (260), bearing (230),  and spacer  ring  (266).    Clean  parts  and  check  for damage and/or wear. 8. Press sleeve bearing (241) complete with steel sleeve   out   of   Figure   4   cover   (3).      It   may   be necessary  to  destroy  the  sleeve  bearing  (241)  to remove it.  Careful not to damage the cover (3).  If necessary   remove   sleeve   by   machining   in   lathe. Chuck  cover  (3)  in  a  lathe  to  assure  maximum total    indicator    reading    (T.I.R.)    of    0.002    in. (0.05mm) at centering diameter (see Figure 4). 9. Remove  the  radial  seal  rings  (400).    The  radial seal  rings  are  metal  encapsulated.    Insert  small screwdriver   in-between   the   seal   ring   and   the cover   (3).      A   twisting   action   will   deform   ring sufficient  to  facilitate  the  removal.    During  the disassembly     the     radial     seal     ring     must     be deformed  in  order  to  remove.    Removed  rings can not be reused. Figure 5 C - Preparation For Assembly In the event the  sleeve  bearing  (241)  and  the  radial seal rings (400) are not removed, continue to Paragraph D. 1. Press  new  sleeve  bearing  (241)  into  cover  (3). Check for run out, refer to Paragraph B item 8. 2. Check  shaft  surface  for  wear  under  seal  rings. After period of operation, it is normal to observe wear  tracks  on  the  shaft  surface  under  the  seal rings.  It is possible to get a second life out of the shaft    by    locating    the    radial    seal    rings    in    a different   position   than   originally   supplied,   see Figure  7.    Old  design  pumps  may  have  3  to  4 mm wide spacers which can be used to achieve the  above  mentioned  arrangement.    Make  sure the rings are installed as shown in Figure 6 or 7, note the reverse position of the outer most radial seal   ring.      Use   of   the   SIHI   Radial   Seal   Ring Gauge will facilitate assembly. 3. Fill  the  space  between  the  sealing  rings,  (400) with  a  high  temperature  grease  with  a  dropping point over 338°F.  (170°C.) such as: -Esso Unirex N3 -Shell Aero Grease No.  16 -Dow Molykote BR-2 Plus -Or Equivalent 4.    Install bearing seal ring (426).  note position. (page 3 - 1146) Figure 4