SERVICE MANUAL Legend for Fig. 23 1 Outlet Port 2 Spring 3 Cap, Top 4 Screw, Cap 3/8"-16x1" 5 Cup, Filter 6 Strainer 7 Nut, 3/8"-16 8 Washer, Lock 3/8"-ext. tooth 9 Nut, 3/8"-16 10 Rod, Support 11 Washer, Lock 3/8"-ext. tooth 12 Nut, 3/8"-16 13 Screw, Cap Socket hd. 3/8"-16x1l" 14 Gasket 15 Spindle 16 Seat, Ring 17 Heater 18 Thermostat 19 Spring 20 Port, Exhaust 21 Ring, Retaining 22 Spring 23 Cup, U 24 Ring, O 25 Piston 26 Port (UNL) Unloader 27 Nut, Unloader 28 Sleeve 29 Cap, Bottom 30 Gasket 31 Gasket 32 Plate, Support 33 Body 34 Deflector 35 Washer 36 Ring, Packing 37 Spring, V 38 Filter 39 Spring 40 Gasket 41 Valve, Safety 42 Spindle 43 Gasket 44 Nut 5. Remove    complete    unloader    valve    assembly including copper gaskets (10). Excessive  accumulation  of  oil  in  the  unloader  assembly indicates that the air compressor requires attention. 6. Examine   unloader   valve   assembly.   If   the unloader   sleeve   (5)   is   nicked,   wrinkled   or   has   axial scratches,    the    unloader    valve    assembly    should    be replaced. The unloader valve assembly if clogged should be cleaned with a good cleansing solvent. 7. Do  not  remove  retaining  ring  (7)  from  unloader spindle (9) since they are serviced  as  an  assembly  with spring (8) and seat ring (1). Fig. 24 Contents of Unloader Valve Kit 1 Ring Seat 6Piston 2 Spring, Large 7Ring, Retaining 3 Cup, U 8Spring, Small 4 Ring, 0 9Spindle, Unloader 5 Sleeve 10Gasket (2 Req’d.) 8. Install   new   "U"   cup   (3)   in   groove   of   unloader piston.  Lips  of  "U"  cup  should  face  away  from spring seat. Do not use sharp tools that may mar or score parts. 9. Apply   a   light   film   of   Item   1   in   LUBRICANT SPECIFICATIONS to  O-ring  (4)  and  position  on unloader nut. 10. Position  the  two  copper  gaskets  (10)  together and lightly coat exposed surfaces with Item 1 of LUBRICANT   SPECIFICATIONS.   Then   position lubricated  gaskets  on  shoulder  of  ring  seat  (1). Gaskets  should  be  on  face  opposite  the  spring (8). 11. Place   gaskets   (10)   followed   by   seat   ring   as- sembly into bottom cap (Item 29 of Fig. 23). 12. Install    unloader    sleeve    (5)    in    unloader    port against  the  seat  ring.  Be  sure  the  12.7  mm  (I") diameter cross hole is next to the seat ring. 13. Position  large  spring  (2)  in  the  sleeve  (5)  with large diameter coil against seat ring. 14. Insert  unloader  piston  (6)  into  unloader  sleeve. Lips of U-cup (3) must face out with spring seat toward spring. The unloader spindle (9) and seat ring (1) is a mated assembly  and  should  not  be disassembled. If either the ring seat or spindle is nicked,   the   entire    mated    assembly    must    be replaced as an assembly. CTS-4079 - CHAPTER XIV - Page 15