IOM-PGR-2
5
phragm to determine whether failed; determine
if op er at ing conditions are exceeding pressure,
pressure drop or temperature limits. If just
replacing the diaphragm, proceed to Step H.9
and skip the following instructions.
12. Grasp pusher post (30.12) and lift up to remove.
Place socket wrench over retainer (30.10) and
rotate CCW to remove from body.
13. Remove seal gasket (30.15), piston seal
(30.14) and a second seal gasket (30.15) from
bore inside the body.
14. To remove the stem (30.8), remove the body
from the vise and slowly turn upside down.
Stem will slide out of the body, Do Not let the
stem fall and hit the floor.
15. Place body (30.1) in a vise with the body cap
(30.3) upwards. Rotate cap bolts (30.20) CCW
to remove bracket and body cap. Remove
cap seal (30.16).
16. Remove return spring (30.11), ball holder
(30.9), and ball (30.22).
17. Place socket wrench over seat (30.7) and
rotate CCW to remove from body.
18. Remove body (30.1) from vise. Clean all
re us able metal parts according to owner's
pro ce dures
H. Pilot Valve Reassembly:
1. Place body (30.1) in a vise flange face down.
2. Apply "Gasoila" or equivalent, thread sealant
to the threads of the seat (30.7). Engage the
seat threads into the body and apply 20 - 25
ft-lbs. torque. Place the ball (30.22), ball holder
(30.9) and return spring (30.11) onto seat.
3. Place the o-ring (30.16) into the groove in
the body cap (30.3) and place onto the body.
Position the bracket on the body cap and re-
install cap bolts (30.20). Make sure the return
spring (30.11) fits inside the bore of the body
cap. Tighten nuts evenly in a star crossing
pattern. Apply 15 - 18 ft-lbs. torque to tighten
the cap bolts.
4. Remove body from the vise. Reinstall body
again in vise with the bolt flange facing up.
5. Insert the stem (30.8) into the center hole of
the body and the seat (30.7), square end first.
6. Place one seal gasket (30.15), one piston seal
(30.14) and one seal gasket (30.15) into the
center bore on top of the stem (30.8). See
Detail "A". Ensure to align the seal and gas-
kets so they are centered inside the threaded
bore hole.
7. Engage the retainer (30.10) threads into the
center bore hole to hold the piston seal and
gaskets in place and apply 75 in-lbs. torque.
to tighten.
8. Insert pusher post (30.12) into retainer (30.10).
9. Place diaphragm (30.13) on bolt flange, cen-
tered between bolt holes. Center the pressure
plate (30.6) on top of the diaphragm.
10. Place range spring (30.4) in center of the
pressure plate (30.6) cup. Apply Mobile XHP
222 grease or equivalent into recessed area
of the spring button (30.5) and place on top of
the range spring. (Also lubricate the threads
of the adjusting screw lightly).
11. Engage threads of the adjusting screw (30.17)
into the spring chamber (30.2) three or four
revolutions and place the spring chamber over
the spring button and spring.
12. Align the match marks on the body and spring
chamber flanges.
NOTE:
Vent hole in the
spring chamber should be directly above the
sense port in the body.
13. Place flange bolts through holes in spring
chamber and body and engage nuts (30.21).
Tighten nuts evenly in a star crossing pattern.
Apply 15 - 18 ft-lbs. torque to finish tightening.
Secure the name plate (30.23) under one of
the flange bolts (30.19) above the "inlet" of
the pilot.
14. Rotate adjusting screw (30.17) CW into the
spring chamber (30.2) to where the nut (30.18)
comes in contact with the top of the spring
chamber. Pilot valve set pressure should
approach the set point prior to removal from
the piping installation. Retighten nut (30.18).
I. Mounting Pilot Valve to Main Valve:
1. Place the bolt holes for the mounting bracket
over the two longer bolts (23) installed through-
out the top of the cover dome (2). Engage
the final two nuts (24) and secure tight.
