SERVICE MANUAL 3. Remove eight cap screws holding top cap (2) to body (8). CAUTION Use  care  in  removing  top  cap  bolts  to prevent  bodily  injury  because  the  cap  is spring   loaded   with   approximately   178 Nm (40 ft.  lbs.). 4. Remove spring (Item 39 in Fig. 23). 5. Remove  all  traces  of  gasket  material  from  top cap and body gasket surfaces (2 & 7).    Discard gasket.      Be   careful   not   to   scratch   or   score gasket  surfaces  and  wash  top  cap  in  cleaning solvent. 6. Remove complete filter assembly. 7. Remove rubber packing ring (7) and discard. 8. Discard   old   stainless   steel   filter.      If   you   are replacing  entire  filter  assembly,  the  entire  filter assembly including filter cup (3), strainer (5) and V-spring (4) may also be discarded. 9. Wash  strainer  (5)  and  filter  cup  (3)  in  cleaning solvent. 10. Assemble stainless steel filter (6) in filter cup (3). Filter should be stretched slightly to fill the space in filter cup. 11. Reinstall   strainer   (5)   with   flat   face   of   strainer towards stainless steel filter. 12. Install     V-spring     (4)     holding     filter     assembly together. 13. Install new packing ring (7) on ledge of body. 14. Position filter assembly into  body  with  large  end down.  The filter must set on packing ring. 15. Install   heavy   spring   (39,   Fig.   23)   with   larger diameter coil against top of filter assembly. 16. Position  new  gasket  (1)  on  body.    Do  not  use gasket cement. 17. Position  top  cap  and  spring  so  that  the  small diameter coil on spring fits groove in top cap. 18. Compress spring and install four 3/8 cap screws (4,  Fig.  23)  into  body.    Each  of  these  four  (4) screws   should   be   engaged   at   least   three   full turns   before   load   on   cap   is   removed.      Cap screws  should  be  equally  spaced.    Then  thread remaining screws into place. Fig. 27  Servicing Filter Assembly 1 Gasket 5 Strainer 2 Top Cap 6 Filter 3 Filter Cup 7 Packing Ring 4 V Spring 19. Tighten all top cap bolts alternately and evenly to 20.4 Nm (15 ft.  lbs.). 20. Reconnect air line to outlet port. 21. Test unit operation following instructions outlined in SERVICE CHECKS. Servicing Thermostatically Controlled Cartridge Type Heater The  current  heat  exchanger  units  contain  a  12 volt 50 watt heater as standard equipment.  This heater requires     a     newly     designed     bottom     cap     which     is completely interchangeable with those in use previously. Use of this new cap may, however, necessitate a change of the deflector assembly if your present bottom cap has the  deflector  attached  to  it   by   screws.      Wrap   around strap    type    heaters,    which    are    NOT    thermostatically controlled   are   available   for   this   old   style   bottom   cap. Refer to Servicing Wrap-Around Strap Type Heater. There    are    two    kits     used     in     servicing     the thermostatically controlled cartridge type heater assembly.  Both heaters are 50 watt, however, one is 12 volt and the other is a 24 volt. Instructions for installing either of the kits are as follows. 1. Refer to the General Instructions. 2. Disconnect    the    electrical    line    from    the    CR BRAKEMASTER heater. 3. Remove  old  cartridge  type  heater  by  loosening set screw for heater on bottom cap. 4. Remove   old   thermostat   from   bottom   cap   by removing the two small screws which retain CTS-4079 - CHAPTER XIV - Page 18