SERVICE MANUAL Fig. 8 Sectional View of E6 Brake Valve 1 SCREW 2 WASHER, Diaphragm 3 DIAPHRAGM, Exhaust 4 COVER, Exhaust 5 RING, Retainer 6 VALVE, Secondary & Exhaust 7 RETAINER, "O" Ring 8 WASHER 9 SPRING, Return 10 BODY, Lower Valve 11 BODY, Upper Valve 12 RING, Seal 13 PISTON, Relay 14 SPRING, Relay Piston 15 VALVE, Primary Inlet & Exhaust 16 PISTON, Primary 17 SPRING, Primary Piston Return 18 SPRING, Rubber 19 RETAINER, Primary Piston 20 SEAT, Spring 21 SPRING, Stem 22 GUIDE, Stem Spring 23 STEM 24 NUT, Spring Seat 25 SCREW, Spring Guide (Not Used) 26 PLUNGER 27 BOOT 28 TREADLE 29 PLATE, Mounting 1. Position  primary  inlet  and  exhaust  assembly  in the   upper   body;   then   install   retaining   ring   to secure  it.    Be  sure  the  retaining  ring  is  seated completely in its groove. 2. Install large and small O-rings on relay piston. 3. Replace  primary  piston  O-ring  in  piston   0-ring groove. 4. Position rubber spring (18), concave  side  down, In primary piston and place spring seat (20), flat side up, over rubber spring. 5. Install primary piston spring seat nut (24) with its hex  closest  to  spring  seat  and  rotate  clockwise until  top  surface  of  spring  seat  is  even  with  top surface of piston (16). 6. Position  primary  piston  return  spring  (17)  in  the upper body piston bore. 7 .Install   primary    piston,    spring    seat    out,    over return spring and press piston into body bore. 8. Place relay piston return spring (14) in the upper body and position relay piston over spring so that the   concave   side   of   the   piston   is   against   the spring (refer to Fig. 8). 9. Compress  both  primary  piston  and  relay  piston into the upper body and hold them compressed, either  manually  or  mechanically  (see  CAUTION under No.  8 in DISASSEMBLY). 10. Place stem (23) through exhaust passage of the lower  body  so  that  threaded  portion  is  visible  at primary piston. 11. Use a screwdriver to engage and hold the slotted head of stem; then position stem spring (21) and spring guide (22) over primary piston. 12. Install ESNA nut on stem and rotate clockwise to 2.3 - 3.4 N.m (20 - 30 in lbs) of torque. 13. Install   primary   piston   retainer   (19)   over   piston making certain all three lock tabs have engaged the outer lip of body. 14. Install secondary inlet and exhaust valve assembly in lower body. 15. Place   exhaust   cover   (4)   on   lower   body   and install four #10-24 machine screws with lockwashers; torque screws to 2.3 - 3.4 N.m (20 - 30 in lbs). 16. Install   exhaust   diaphragm   (3)   and   diaphragm washer  (2)  to  exhaust  cover  using  Phillips  head screw and lockwashers. CTS-4079-CHAPTER IV- - Page 8