Meggitt F251 Series User manual

Maintenance Manual
HYDRANT COUPLER
F251 Series
MMF251
Revision 4.0
28 February 2014
Meggitt (North Hollywood), Inc. Proprietary Information
The information contained in this document is disclosed in confidence. It is the property of Meggitt (North Hollywood), Inc. and shall not be used,
disclosed to others, or reproduced in whole or in part without the express written consent of Meggitt (North Hollywood), Inc. If consent is given, this
notice shall appear in any such reproduction. These commodities, technology, or software were exported from the United States in accordance with
the export administration regulations. Diversion contrary to U.S. law is prohibited.
SENSITIVE BUT UNCLASSIFIED-EXPORT CONTROLLED-EAR RESTRICTED.
These commodities, technology or software are exported from the United States of America in accordance with the Export Administration
Regulations. ECCN EAR99. Diversion contrary to U.S. law is prohibited.
Copyright © 2014 Meggitt (North Hollywood), Inc.
Shown with additional
coupler modifications

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REVISION RECORD
Keep this record in the front of the manual. When you get the revisions, put the revised pages in the
manual. Write the revision number, date issued and your initials on this page.
REV NO. PAGES
AFFECTED DESCRIPTION OF CHANGE DATE APPROVED BY
1.0 ALL Initial Release 05/31/2011 A.B
1.1 ALL - 06/06/2011 A.B
2.0 ALL - 09/30/2011 A.B
2.1 ALL - 04/20/2012 A.B
3.0 ALL See DCN 07/30/2013 A.B
4.0 1, 9-12, 14, 18 & 19 See DCN 3/19/14 A.B

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TABLE OF CONTENTS
SUBJECT PAGE
IMPORTANT SAFETY INSTRUCTIONS ........................................................................................................A
INTRODUCTION............................................................................................................................................. 1
DESCRIPTION AND OPERATION................................................................................................................. 2
FAULT ISOLATION......................................................................................................................................... 5
DISASSEMBLY............................................................................................................................................... 6
CLEANING.................................................................................................................................................... 10
INSPECTION ................................................................................................................................................ 12
ASSEMBLY................................................................................................................................................... 13
ILLUSTRATED PARTS LIST ........................................................................................................................ 17
LIST OF ILLUSTRATIONS
FIGURE PAGE
Figure 1.Hydrant Coupler............................................................................................................................ 3
Figure 2.Coupler Section Assembly.......................................................................................................... 14
LIST OF TABLES
TABLE PAGE
Table 1Leading Particulars........................................................................................................................ 4
Table 2Fault Isolation................................................................................................................................ 5
Table 3Recommended Cleaning Materials ............................................................................................. 10
Table 4Component Checks..................................................................................................................... 12
Table 5Recommended Assembly Materials............................................................................................ 13

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IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS!
This manual contains important instructions that shall be followed during installation and maintenance of the
Hydrant Coupler. The following are general safety precautions that are not related to specific procedures
and therefore do not appear elsewhere in this publication. These are recommended precautions that
personnel must understand and apply during maintenance.
The coupler is a mechanical device and can be dangerous if not correctly operated or maintained.
Safety Alert Symbols
Safety alert symbols are used in this manual to identify potential or immediate personal injury hazards. The
safety alert symbol words are explained below:
- indicates an imminently hazardous situation which, if not
avoided, will result in injury or serious injury.
- indicates a potentially hazardous situation which, if not avoided,
could result in injury or serious injury.
- indicates a potentially hazardous situation which, if not avoided,
may result in minor or moderate injury.
- used without the safety alert symbol indicates a potentially
hazardous situation which, if not avoided, may result in
property damage.
WEAR PROTECTIVE CLOTHING
Wear protective clothing (gloves, apron, etc.) approved for the materials and tools being used.

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Equipment Safety Information
The following safety information briefly discusses hazards peculiar to the equipment, which are likely to be
encountered during maintenance activity.
COUPLER INSTALLATION AND OPERATION PRECAUTIONS
The design of the piping system must provide adequate pressure to prevent exceeding the limits of the
coupler.
Make sure the coupler orientation is correct and install the coupler in-line with the flanges. Make sure
the piping flanges are correctly positioned and spaced. Do not force the piping in order to fit the
coupler.
Make sure the coupler operates correctly after installation.
Do not exceed the pressure limits of the coupler.
COUPLER MAINTENANCE PRECAUTIONS
Do not loosen any fasteners or attempt to remove the coupler from the line until all pressure is isolated
and released from the system.
Use only authorized replacement parts or hardware.

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INTRODUCTION
NOTE: The F251 Hydrant Coupler is a direct upgrade replacement for the F250 coupler. The F251
Coupler complies with the API Standard 1584 3rd edition breakaway requirements. The shaft and
seals are designed to improve safety, reliability and maintainability.
1. General
The information and procedures contained in this manual have been prepared to assist qualified repair
personnel in off-aircraft maintenance of the Hydrant Coupler (coupler). The instructions provide
information necessary to perform maintenance functions. The Coupler is manufactured by Meggitt
(North Hollywood), Inc., 12838 Saticoy Street, North Hollywood, California 91605.
2. Scope
The instructions contained in this manual do not claim to cover all details or variations in equipment.
They do not provide for every problem that could occur during installation, operation, or maintenance. If
further information is required, contact Meggitt (North Hollywood), Inc., Product Support Department.
3. Standard Shop Practices
Use approved procedures and safety precautions to prevent damage to the equipment and injury to
personnel.
4. Weights and Measurements
Weights and measurements in this manual are expressed in both English (U.S. customary) and Metric
(SI) units.
5. Revision Service
This manual will be revised, as necessary, to reflect current information.

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DESCRIPTION AND OPERATION
1. Description
The Hydrant Coupler (coupler) (see Figure 1) provides the means of connecting 4-inch hydrants and
adapters conforming to API Standard 1584. The various optional configurations permit the use of
several thread and hose sizes. The major functional components of the hydrant coupler are the
swiveling outlet adapter, the elbow and the coupler body section.
2. Installation/Operation
A. Install Coupler on Hydrant
The coupler may be connected to the hydrant adapter by pressing it downward onto the adapter.
This actuates the six locking lugs, and releases the shroud. The shroud slides downward and holds
the locking lugs in their locked position. If product selection is installed, the shroud will need to be
rotated to align the product selection screws with the slots in the shroud.
B. Operate the Coupler
DO NOT OPEN THE COUPLER WITHOUT BEING CONNECTED TO AN
ADAPTER. SLEEVE SEAL DAMAGE MAY OCCUR.
After installation, to open the coupler, rotate the handle to the OPEN position. To close the coupler,
rotate the handle to the CLOSED position.
C. Remove Coupler from Hydrant
With the hydrant closed, the coupling may be disengaged from the hydrant adapter by rotating its
operating handle to the CLOSED position and pulling back the shroud to disengage the locking
lugs.
D. Remove Coupler and Elbow from Hose
Pull the safety ring from its groove and slide it back to the retaining ring. Do not remove the safety
ring. Unscrew the four retaining screws approximately 3 full turns. Slide the retainer back to the
safety ring. The elbow can now be separated from the hose.

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Figure 1. Hydrant Coupler

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3. Leading Particulars (Refer to Table 1)
Table 1 Leading Particulars
Service ........................................................................................................................Automotive and Aviation Fuels
Operating Pressure
Maximum Working...............................................................................................................200 psi (1380 kPa)
Peak Surge..........................................................................................................................305 psi (2100 kPa)
Pressure Drop (connected to F368 Hydrant)
(approximate) ...................................................................................13 psi at 1200 gpm (90 kPa at 4500 lpm)
Fluid Temperature..............................................................................................................–40 to 160°F (-40 to 71°C)
Ambient .............................................................................................................................–40 to 160°F (-40 to 71°C)
Weights (approximate)
Basic.................................................................................................................................16.6 pounds (6.2 kg)
Mod A – Hydrant 4 inch Coupler for CCMZ7300M2/ CCMZ7309M2
Pressure Control Elbow.....................................................................................16.6 pounds (9.7 kg)
Mod B – with 90° Elbow + F597A 4 inch NPT Swivel......................................................24.4 pounds (9.7 kg)
Mod C – with 90° Elbow + F597B 4 inch BSPPL Swivel................................................25.2 pounds (10.1 kg)
Mod D – with 90° Elbow + F597C 3 inch NPT Swivel....................................................25.2 pounds (10.1 kg)
Mod E – with 90° Elbow + F597D 3 inch BSPPL Swivel................................................ 25.2 pounds (10.1 kg)
Mod F – with 90° Elbow + F597E 2.5 inch NPT Swivel .................................................25.2 pounds (10.1 kg)
Mod G – with 90° Elbow + F597F 2.5 inch BSPPL Swivel...............................................24.4 pounds (9.7 kg)
Mod H – with 90° Elbow + F597G 4 inch NPSM Swivel ..................................................21.9 pounds (8.6 kg)
Mod J – with 90° Elbow for F597 Swivel........................................................................+0.1 pound (+0,05 kg)
Mod K – (Use only with MOD B thru J) + 0.75 inch NPT THD in Elbow, with plug......... 21.9 pounds (8.6 kg)
Mod L – Add Product Selection Position 4........................................................................... No weight change
Mod M – With 90° Elbow + F597M 4 inch NPSH.............................................................24.4 pounds (9.7 kg)
Mod R – Viton Seals............................................................................................................. No weight change

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FAULT ISOLATION
1. General
Refer to Table 2 for fault isolation information. Locate suspected faulty component and take appropriate
remedial action.
Table 2 Fault Isolation
FAULT POSSIBLE CAUSE CORRECTIVE ACTION
Leakage from outlet adapter Damaged or worn bearing ring,
(IPL Figure 2, 6), seal (IPL Figure 1,
15) or O-ring (21)
Check condition and if necessary
replace the bearing ring, seal,
and/or O-ring.
Leakage from elbow flange Damaged or worn O-ring (13) Check condition and if necessary
replace the O-ring.
Leakage past handle shaft Damaged or worn O-ring (33) Check condition and if necessary
replace the O-ring.
Leakage past poppet when closed Damaged or worn O-ring ( 21) Check condition and if necessary
replace the O-ring.
Damaged or worn sleeve assembly (12) Check condition and if necessary
replace the seat.
Damaged or wear on seat face of
poppet (9) Check condition and if necessary replace poppet.
Leakage at hydrant adapter when
open Damaged or worn O-ring (21) Check condition and if necessary replace the O-ring.
Damaged or worn seal (15) Check condition and if necessary
replace the seal.

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DISASSEMBLY
1. Overhaul Parts Kits
Refer to the ILLUSTRATED PARTS LIST section for the Overhaul Parts Kit information.
2. Disassemble the Hydrant Coupler
A. (Mods B – K and M) Swivel Assembly Removal (See IPL Figure 2)
Remove the Swivel Assembly from the Coupler Elbow as follows:
1. (Mod M) Remove and discard seal (1) from its groove on the outlet adapter attached to the
Swivel body.
2. Remove safety rings (2) from its groove on locking ring (5).
3. Loosen screws (3) just enough to allow the locking ring (5) to slide back to safety ring (2).
4. The swivel assembly can now be pulled off of the elbow (14).
Note: The ring (7) can be replaced without further disassembly.
B. (Mods B – K and M) Disassemble Swivel Assembly (See IPL Figure 2)
1. Remove safety rings (2) from its groove on locking ring (5). Slide safety rings (2) and locking
ring (5) from body (9).
2. Remove bearing balls (8) and ring (7).
C. (Mods B – K and M) Elbow Removal (See IPL Figure 2)
1. Remove screws (10), washers (11), nuts (12), elbow (14) and O-ring (13) from the Hydrant
Coupler Assembly (see IPL Figure 1). Discard O-ring (13).

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D. Disassemble the Coupler Assembly (See IPL Figure 1)
Note: Before disassembly; if coupler assembly is equipped with elbow (IPL Figure 2, 14);
remove screws (10), washers (11) and nuts (12) from coupler assembly.
1. Remove dust cover assembly (1) from shroud (3).
2. Use an API-style adapter without a poppet to release the latching lugs (7). (A 6.0 inch
(152 mm) outside diameter x 4.25 inch (108 mm) inside diameter x 3.0 inch (76 mm) long tube
may be used as an alternate for the adapter.)
Note: Alternate method to release the latching lugs (7) is to depress one lug by hand then
slide a thin plate or a small Allen wrench between the back of the lug and the
shroud (3) to prevent the lug from catching in the groove. Repeat this step for all lugs
to release shroud (3) from body (37). Do step 4 after using this method.
3. Put the coupler assembly on the adapter. Press the coupler assembly down until the latching
lugs release the shroud. Slide the shroud down as far as it will go.
4. Rotate handle (17) about 45 degrees to the OPEN position.
5. Remove screw (10) from poppet (9). Remove poppet (9) from hinge (32).
6. Turn the coupler and gently tap the sleeve assembly (12) and springs (11) from body (37).
7. Pry the seal retainer (14) from the sleeve assembly (12).
8. Remove and discard seal (15) and O-ring (13) from the sleeve assembly (12).
9. Rotate handle (17) to the CLOSED position.
10. Remove cotter pin (23), washer (24), and pin (26) from crank (27). Discard cotter pin (23).
11. Remove links (31) and hinge (32) out of body (37).
12. Use a 0.06 inch (1.5 mm) diameter wire to push pin (25) out of the crank (27).
13. Drive pin (18) out of body (37).

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14. Remove together; handle (17) felt wiper (18), bushing (20), O-ring (21), shaft (22), and crank
(27) from body (37).
Note: Look at the relative positions of the handle (17) and the crank (27) for assembly
reference.
15. Drive pin (16) out of handle (17).
16. Remove handle (17), felt wiper (19), bushing (20) and O-ring (21) from shaft (22). Discard
O-ring (21).
17. Remove cotter pin (28), washer (29), pin (30) and links (31) from hinge (32). Discard cotter
pin (28).
18. Remove and discard O-ring (33) from hinge (32).
19. Remove together both; guard (2) and shroud (3) from body (37).
20. Remove felt wiper (4) from shroud (3).
21. Remove springs (8) and latching lugs (7) in body (37) as follows:
Note: Long nose pliers may be used to pull the spring loop during the removal of a spring in
the body, but be careful to avoid damaging the spring. The wire shall not be marked
or scratched.
a. Drive spring tangs out of the latching / locking lug groove.
b. Pull the loop of spring (8) from the hole in body (37), with the two tangs resting on the top
surface. Pull the spring in as far as possible, so the two tangs move away from the body
surface. As the loop of the spring shall be a tight press fit in the hole, make sure the spring
is removed gently and carefully from the body, to avoid any damage to it. Repeat for each
of the springs (8) and locking lugs (7).
22. Drive groove pin (5) out of latching lug (7) and shear pin (6). Remove shear pin (6) from
latching lug (7). Repeat for remaining lugs.

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23. Check condition of shear pin (6), if bent or cracked; discard. Check groove dimension as
follows:
a. (Mods: Basic,B-K,M,R: p/n 430141, Gold Shear Pin) The gold shear pin (6) groove
dimensions shall measure; Ø0.0245 ±0.0005 in. at 2 places. If measurement is out of
tolerance, discard gold shear pin (6).
b. (Mod A: p/n 430220, Red Shear Pin) The red shear pin (6) groove dimensions shall
measure; Ø0.02565 ±0.0005 in. at 2 places. If measurement is out of tolerance, discard
red shear pin (6).
24. Check condition of bushing (34), if worn do as follows:
a. Use a 3/8-16UNC, 6-1/2 inch long bolt threaded into the bushing as a draw-bolt and
remove bushing (34) from the body (37). Discard bushing (34).
25. Remove screw (36) and spacer (35) from body (37). Check spacer (35) thickness as follows:
a. The spacer (35) thickness shall measure; 0.063 ±0.001 inch. If thickness is out of
tolerance, discard spacer (35).
26. Check condition of guard (2), if worn do as follows:
a. Use a sharp bladed tool to cut the guard (2) from the shroud (3). Discard guard (2).

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CLEANING
1. Cleaning Materials
Refer to Table 3 for recommended cleaning materials. Suitable equivalent cleaning materials may be
substituted for the items listed.
Table 3 Recommended Cleaning Materials
DESCRIPTION SPECIFICATION SOURCE
Alcohol, Isopropyl ASTM D770 Commercially available
Bags, Plastic - Commercially available
Brush, Bristle, Stiff, Non-metallic - Commercially available
Pick, Teflon - Commercially available
Solvent, Dry Cleaning P-D-680, Type 2 Commercially available
Tissues, Lint-free - Commercially available
2. Cleaning Procedures
DRY CLEANING SOLVENT IS A HARZARDOUS MATERIAL. BEFORE
USE, READ AND OBEY THE MATERIAL SAFETY DATA SHEET (MSDS)
INSTRUCTIONS FOR CORRECT HANDLING. FAILURE TO OBEY THIS
WARNING MAY RESULT IN PERSONAL INJURY, LONG TERM HEALTH
HAZARDS OR DEATH.
A. Clean all metal parts by washing thoroughly in dry cleaning solvent. Remove stubborn deposits by
scrubbing with a nonmetallic stiff bristle brush. Brush all threaded areas. Use a Teflon pick to
remove obstructions from the ports, the seal or packing grooves and the flow passages.
B. Clean all of the non-metallic parts by wiping them with clean lint-free tissues slightly moistened with
isopropyl alcohol.
Note: All parts must be free of corrosion, dirt, grease, oil or any other foreign matter.

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WEAR EYE PROTECTION WHEN USING COMPRESSED AIR. DO NOT
DIRECT AIRSTREAM AT PERSONNEL OR LIGHT METAL PARTS.
C. Dry parts with clean lint-free tissues or clean, dry compressed air.
D. Package clean parts in plastic bags.

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INSPECTION
1. General
A. Under strong light and magnification, Look at all parts in accordance with the general criteria
specified in Table 4.
B. Repair minor damage in accordance with local directives. If damage is major or beyond simple
repair, replace the part.
2. Component Checks (Refer to Table 4)
Table 4 Component Checks
DESCRIPTION CHECK CRITERIA
General Look at all parts as applicable for nicks, cracks, cuts, burrs, corrosion,
breaks, scoring, chafing, scarring, deformation, dents, thread damage,
or any other obvious defects. Make sure the ports, passages, recesses
and sealing grooves are clean and are not blocked.
Make sure all sealing and seating surfaces are free from damage or
corrosion.

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ASSEMBLY
1. Overhaul Replacement Parts
Refer to the ILLUSTRATED PARTS LIST section for recommended replacements parts information.
2. Assembly Materials
Refer to Table 5 for recommended assembly materials. Suitable equivalent materials may be
substituted for the items listed.
Table 5 Recommended Assembly Materials
DESCRIPTION SPECIFICATION SOURCE
Petroleum Jelly – – Commercially available
Thread Locker Loctite® 262 Commercially available
3. Assemble the Hydrant Coupler
A. Lubrication
Before assembly, lightly lubricate all of the O-rings and seals with petroleum jelly.
B. Assemble the Coupler Section (See IPL Figure 1)
1. If bushing (34) was discarded, press a new bushing into the body (37).
DO NOT TOUCH HOT SURFACES WITH BARE HANDS. USE HEAT
RESISTANT INSULATED GLOVES WHEN HANDLING HOT
COMPONENTS.
2. If guard (2) was discarded from shroud (3), heat a new guard (2) in an oven at 150°F for 3 to 5
minutes. Use gloves to handle the guard (2) and install onto shroud (3).

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3. Install shear pin (6) into latching lug (7). Install pin, groove (5) thru latching lug (7) to shear
pin (6). Repeat for remaining lugs.
Note: Gold Shear pins shall be used on F251 couplers mated on the F239 pressure control
coupler assembly.
Red shear pins shall be used on F251A couplers mated to the CCMY8500M3
pressure control coupler assembly.
4. Install springs (8) and latching lugs (7) in body (37) as follows:
Note: Long nose pliers may be used to close the spring loop during installation of a spring
in the body, but be careful to avoid damaging the spring. The wire shall not be
marked or scratched.
b. Push the loop of spring (8) into the hole in body (37), with the two tangs resting on the top
surface. Push the spring in as far as possible, so the two tangs contact the body surface.
The loop of the spring shall be a tight press fit in the hole.
c. Position latching lug (7) in its groove on body (37), spring anchor end inward to contact
the ends of the two tangs of spring (8). Lift and place the ends of the spring tangs into the
groove of the locking lug. Press the locking lug inward and rotate it into position. Make
sure that both of the spring tangs are still in their correct positions and that latching lug (7)
rotates freely. Repeat for each of the springs (8) and locking lugs (7).
Figure 2. Coupler Section Assembly

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5. Install felt wiper (4) in wiper groove of shroud (3).
6. Install shroud (3) on body (37). Make sure the latching lugs (7) are seated correctly for the
shroud to slide past.
7. Install seal (15) in seal groove on sleeve assembly (12) and secure with retainer (14). Install
O-ring (13) in O-ring groove of sleeve assembly (12).
8. Assemble links (31), clevis pin (30), washer (29) and cotter pin (28) on hinge (32).
MAKE SURE PIN (16) IS FLUSH OR BELOW THE SURFACE OF THE
HANDLE (17). FAILURE TO OBEY THIS CAUTION MAY CAUSE
DAMAGE TO PIN (16).
9. Apply petroleum jelly to new O-ring (21), and install O-ring (21), bushing (20), wiper (19) and
handle (17) on shaft (22). Secure handle (17) to the shaft (22) with pin (16).
10. Install shaft assembly into body (37) and through crank (27). Make sure crank (27) is oriented
with the hole for pin (26) farthest away from the flat of handle (17).
11. Drive pin (18) into the pin bore of body (37) to secure shaft assembly.
12. Install wave washer spring (11) and sleeve assembly (12) into body (37).
13. Rotate handle (17) to the CLOSED position. Align hole on crank (27) with hole on shaft (22)
and install pin (25) through crank (27) and shaft (22).
14. Put body (37) on the API-style Adapter (or equivalent) used during disassembly of the coupler.
Slide shroud (3) past body (37).
Note: The Allen wrench method may be used to prevent latching lugs (7) from catching onto
shroud (3) to slide shroud (3) past body (37).
15. Locate bow of links (31) on the hinge (32) and holes on top of link (31) with crank (27). Install
pin (26), washer (24) and cotter pin (23). The bow of links (31) shall be pointing 180° from
operating handle (17), when the handle is in the CLOSED position.
16. Rotate the handle (17) to the OPEN position. Install O-ring (33) on to hinge (32). Install poppet
(9) on to hinge (32). Apply thread lock on screws (10) and secure poppet (9) with screws (10),
and torque to 19 ±2 in-lbs.
17. Rotate handle to the CLOSED position; slide the shroud (3) up to the handle (17) until the
locks are engaged.