Emerson Fisher 161AY Series Instruction Manual page 21

6. Stack the control spring (key 9), control spring seat
(key 8) and diaphragm limiter (key 10) (if used) on
the diaphragm assembly (key 7). If used, make sure
the diaphragm limiter is installed beveled side up on
Types 161EB and 161EBM pilots with 200 to
350 psig / 13.8 to 24.1 bar outlet pressure range.
Lightly apply lubricant to the control spring seat.
7. Install the spring case (key 2) on the body (key 1)
with the vent (key 18) properly oriented. Make
sure the vent is not directly over inlet or outlet
piping due to possible icing. Install the machine
screws (key 13, not shown), using a crisscross
pattern, torque them to 5 to 7 ft-lbs / 6.8 to 9.5 N•m
for stainless steel bodies and 2 to 3 ft-lbs / 2.7
to 4.1 N•m for aluminum bodies. Lubricate the
adjusting screw threads.
8. When maintenance is complete, refer to the
Startup and Adjustment section to put the regulator
back into operation and adjust the pressure setting.
Tighten the locknut (key 12), replace the closing
cap gasket (key 17) if necessary and install the
closing cap (key 16).
161AY Series Pilots (Figure 20)
Body Area
1. Use this procedure to gain access to the disk
assembly, orifice and body O-ring. All pressure
must be released from the diaphragm casing and
the disk assembly must be open, before these
steps can be performed.
2. Remove the cap screws (key 2) and separate the
diaphragm casing (key 4) from the body (key 1).
3. Remove body seal O-ring (key 11) and the back-
up ring (key 50). Inspect the body seal O-ring and
replace if necessary.
4. Inspect and replace the orifice (key 5) if necessary.
Lubricate the threads of the replacement orifice
with a good grade of light grease and install with
29 to 37 ft-lbs / 39 to 50 N•m of torque.
5. Remove the cotter pin (key 15) if it is necessary to
replace the disk assembly (key 13) or the throat
seal O-ring (key 31) of a Type 161AYM.
6. For a Type 161AYM, inspect the throat seal
O-ring (key 31) and remove the machine screw
(key 33). Replace O-ring if necessary.
7. Install the disk assembly (key 13) and secure
it with the cotter pin (key 15).
8. Place back-up ring (key 50) into the body (key 1)
then place the body seal O-ring (key 11) into the body.
Figure 12. Expanded View of the Body Area
Showing the O-ring and Back-up Ring Placement
9. Place the diaphragm casing (key 4) on the body
(key 1). Secure the diaphragm casing to the body
with the cap screws (key 2).
Diaphragm and Spring Case Area
Use this procedure to change the control spring and to
inspect, clean or replace parts in the spring case and
diaphragm assembly.
To Change the Control Spring:
1. Remove the closing cap (key 22) and turn the
adjusting screw (key 35) counterclockwise until
all compression is removed from the control
spring (key 6).
2. Change the control spring (key 6) to match the
desired spring range.
3. Replace the adjusting screw (key 35).
4. Install the replacement closing cap gasket (key 25)
if necessary and reinstall the closing cap (key 22).
5. If the spring was changed, be sure to change
the stamped spring range on the nameplate.
To Disassemble and Reassemble Diaphragm Parts
1. Remove the closing cap (key 22) and turn adjusting
screw (key 35) counterclockwise to remove adjusting
screw, baffle plate (key 56) and control spring (key 6).
2. Remove the spring case hex nuts (key 23, not
shown), cap screws (key 24) and spring case (key 3).
3. Remove the diaphragm (key 10) and attached
parts by tilting them so that the pusher post (key 8)
slips off the lever assembly (key 16). To separate
the diaphragm (key 10) from the attached parts,
unscrew the machine screw (key 38) from the
pusher post (key 8).
4. Inspect the pusher post (key 8) and the body seal
O-ring (key 11), replace if required.
5. Remove hex nut (key 21) to separate the
diaphragm (key 10) and attached parts.
Type EZR
BODY SEAL O-RING (KEY 11)
BACK-UP RING (KEY 50)
BODY (KEY 1)
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