TM 5-3895-374-24-2 ASSEMBLY Optional Mechanical Seal (Synthetic Rubber Bellows Type) Synthetic rubber bellows mechanical seals, the style shown in Figures  11,  12,  &  13,  may  be  installed  as  alternate  to  the standard Teflon seal as the application warrants.  These seals are dependent upon friction to drive them and, therefore, there are no set screws to tighten.  No spacer is used on Model "K" between rotor and synthetic rubber bellows seal. Prior  to  installing  rotating  portion  of  mechanical  seal,  prepare and   organize   rotor   shaft,   head   and   idler   assemblies   and appropriate gaskets for quick assembly. Once  rotating  portion  of  mechanical  seal  is  installed  on  rotor shaft, it is necessary to assemble parts as quickly as possible to   insure   that   seal   does   not   stick   to   shaft   in   wrong   axial position.    The  seal  should  be  expected  to  stick  to  the  shaft after several minutes setting time. Never touch sealing faces with anything except clean hands or clean  cloth.    Minute  particles  can  scratch  the  seal  faces  and cause leakage. 1. Clean rotor hub and bracket seal housing bore.  Make sure   both   are   free   from   dirt   and   grit.      Coat   outer diameter     of seal seat and inner diameter of sealhousing  bore  with  nondetergent  SAE  30  weight oil. 2. Start  seal  seat  in  seal  housing  bore,  refer  to  Figure 11.    If  force  is  necessary,  protect  seal  face  with  a clean cardboard disc and gently tap it in place with a piece of wood. FIGURE 11. 3. Place   tapered   installation   sleeve   on   shaft,   refer   to Figure 12.  Sleeve is furnished with H, HL, K, KK, L, LQ and LL size replacement mechanical seals.  Coat rotor    shaft,    tapered    installation    sleeve    and    inner diameter  of  mechanical  seal  rotary  member  with  a generous amount of non-detergent SAE 30 weight oil. Petrolatum may be used but grease is not recommended. FIGURE 12. 4. Place seal spring on shaft against rotor hub.  Refer to Figure 13. 5. Slide  rotary  member,  lapped  contact  surface  facing away  from  spring,  over  installation  sleeve  on  shaft until  it  is  against  spring.    Remove  seal  installation sleeve. Do not compress spring. 6. Coat rotor shaft with non-detergent SAE 30 weight oil. Start  end  of  shaft  in  bracket  bushing  and  turn  from right to left,  slowly pushing until the ends of the rotor teeth are just below the face of the casing. Leave  the  rotor  in  this  position.    Withdrawal  of  rotor and shaft may displace the carbon seal rotating face and result in damage to the seal. FIGURE 13. AT THIS POINT, FINISH ASSEMBLY PROCEDURES STARTING AT STEP 10, PAGE 9. page 3-1220