TM 10-4320-321-13&P FORM 5S2583 MODELS 2P121 THRU 2P128 & WP373 THRU 2P380 01615 Maintenance (Continued) Figure 7.  Mechanical Seal Replacement (Teflon Seal Shown) 3. Unscrew    impeller    (Ref.    No.    14)    from    the    shaft adapter.  Remove  the  impeller  O-ring  (Ref.  No.  15) and   clear   all   sediment   from   impeller.   Inspect   the impeller O-ring, replace if deeply scarred or worn. NOTE: DO NOT remove or adjust shaft adapter (Ref. No. 3). 4. Pry  seal  seat  (Ref.  No.  12)  from  recess  of  impeller. Use caution so as not to damage or remove seal seat pin (Ref. No. 13) on Teflon seal equipped units. 5. Remove the adapter and casing cover (Ref. Nos. 5 & 8) by unthreading four fasteners (Ref. Nos. 7 & 22; two of each). 6. Press seal cartridge (Ref. No. 11) from the rear of the casing cover. 7. Clean  casing  cover  and  impeller  seal  recesses  and shaft  adapter.  Make  certain  all  surfaces  are  perfectly clean before installing new seal parts. CAUTION:  Handle  seal  parts  with  extreme  caution  and  keep  them clean.  Do  not  touch  seal  faces  (either  ceramic  or  carbon)  with  your hands. Do not apply lubricants on seal faces. This could cause a leak or premature seal failure. 8. Apply  a  light  coat  of  sealing  compound  to  new  seal cartridge  (See  Figure  7)  and  press  it  into  the  casing cover recess using the proper size tube or installation tool (See Figure 8). DO NOT press on carbon face or top  of  metal  cup  of  the  seal  cartridge.  Install  using flange only. 9. Slide  the  assembled  adapter  and  casing  cover  (Ref. Nos.  5  &  8)  onto  motor  mounting  face.  Fasten  with four fasteners (Ref. Nos. 7 & 22; two of each), making sure that the mounting foot (Ref. No. 23) is in place. 10.    Press  new  seal  seat  (Ref.  No.  12)  squarely  into  the impeller  recess.  Align  slot  in  the  seal  seat  with  seal seat pin (Ref. No. 13) on Teflon equipped units. Avoid scratching the ceramic surface. NOTE:   Use   a   soft,   clean   piece   of   cloth   on   seal   seat   face   when installing to prevent marring. 11.   Screw the impeller back in place, tightening until it is firmly seated. 12.   Install the impeller 0-ring (Ref. No. 15) and install and tighten impeller locknut (Ref. No. 16). 13.    Reinstall  O-ring  seal  (Ref.  No.  10)  on  casing  cover rabbet.    Remount    casing    (Ref.    No.    17)    with    six fasteners (Ref. No. 9). 14.   If 3/16" hex key (Allen wrench) was inserted into the shaft  adapter  clamp  screw  to  prevent  shaft  rotation, remove it. Pump may now be returned to service. NOTE:   Always   flush   pump   thoroughly   before   use   so   as   not   to contaminate liquid being pumped. IMPELLER CLEARANCE ADJUSTMENT When  installing  replacement  motor,  shaft  adapter (Ref.  No.  3),  adapter  (Ref.  No.  5),  casing  cover (Ref. No. 8), impeller (Ref. No. 14) or casing (Ref. No.    17),    it    may    be    necessary    to    adjust    the clearance between the impeller and casing faces. NOTE: A proper running clearance is less than 0.021". CAUTION:  If  the  impeller  (Ref.  No.  14)  is  replaced,  the  seal assembly   should   also   be   replaced   as   the   seal   is   usually damaged  in  disassembly.  Also  replace  Teflon  washer  (Ref. No. 15). 1. After the replacement components have been installed,   reassemble   the   pump   as   described under    "Mechanical    Seal    Replacement".    DO NOT remount pump casing (Ref. No. 17) at this time. 2. Loosen   lock   screws   (Ref.   No.   1)   in   shaft adapter clamp (Ref. No. 2) as the impeller will move in and out freely. Leave loose but do not remove   the   assembly   from   the   motor   shaft (screws are accessible through adapter openings). 3. Stand  the  pump  up  on  motor  end  if  possible and place a 0.020" feeler gauge in the face of the  impeller  (if  feeler  gauge  is  not  available, use five to six thicknesses of newspaper. Make sure impeller and casing are absolutely dry and clean).   With   pump   still   on   end,   remount   the casing  (Ref.  No.  17)  tightening  fasteners  (Ref. No. 9) evenly. 4. Make  certain  the  full  width  of  shaft  adapter clamp (Ref. No. 2) is in place on shaft adapter and the split in the shaft adapter (Ref. No. 3) is aligned with the part between the clamp halves and retighten lock screws (Ref. No. 1). 5. Unthread  fasteners  (Ref.  No.  9)  and  remove casing (Ref. No. 17). Remove feeler gauge (or newspaper pieces). Then mount casing making certain all fasteners are tight. NOTE: Make certain that O-ring seal (Ref. No. 10) is in place. 6. Check  shaft  to  make  sure  it  turns  freely  (turn shaft with shaft adapter clamp). This procedure should insure the proper running clearance and will   deliver   maximum   performance   from   the pump. NOTE: If shaft will not turn, remove casing (Ref. No. 17) and repeat above procedure beginning with step 2. Figure 8 - Seal Installation Tool -7-