Wabtec ABDX-SS 664742 Manual

Operation & Maintenance Instruction
August, 2003Page 1 of 24
4225-50, S.6
NOTE: The following description and
operation is based on this device and
its components being new or this
device and its components having
been repaired, tested, installed and
maintained in accordance with
instructions issued by this and any
other applicable Wabtec Corporation
publications.
WARNING: At the time any part is
replaced in this device, the operation of
the complete device must pass a
series of tests prescribed in the latest
issue of the applicable Wabtec Test
Specification. At the time this device is
applied to the brake equipment
arrangement, a stationary vehicle test
must be made to ensure that this device
functions properly in the total brake
equipment arrangement. (Consult your
local Wabtec Corporation
Representative for identity of the test
specification, with latest revision date,
that covers this device.)
IMPORTANT: Only Wabtec Corporation
supplied parts are to be used in the
repair of this device in order to obtain
satisfactory operation. Commercially
available non-O.E.M. parts are
unacceptable.
NOTE: The part numbers and their
associated descriptions are the
property of Wabtec Corporation and may
not be replicated in any manner or form
without the prior sole written consent of
an Officer of Wabtec Corporation.
ABDX®-SS CONTROL VALVE, PART NO. 664742
ABDX®-SS ALUMINUM SERVICE PORTION
ABDX®-SS ALUMINUM EMERGENCY PORTION
AUGUST, 2003
® Registered Trademark of Wabtec Corporation
© 2003 WABCO Freight Car Products. A Wabtec Company. All rights reserved
IMPORTANT: This valve is NOT to be applied to freight cars that are assigned to
Interchange Service on the North America Continent Railroads.

Operation & Maintenance Instruction
Page 2 of 24
August, 2003
4225-50, S.6
1.0 DESCRIPTION
The AB Single Capacity Freight Car Air Brake Equipment
with the ABDX Type Control Valve is functionally compatible
with equipments using the AB, ABD or the ABDW Control
Valve. Correct style ofABDX Control Valve must be applied
to specific length cars.
The ABDX Type Control Valve improves service braking by
providing both a shorter response time and a shorter brake
cylinder pressure build up time. The initial quick service
function has been improved through a new service piston,
diaphragm and diaphragm clamping arrangement.
Other benefits of the ABDX Type Control Valve include
improved undesired emergency (UDE) protection, improved
protection against leakage, and the elimination of the need
for auxiliary continuous quick service valves.
1.1 PARTS OF THE EQUIPMENT
The following is a description of the Control Valve which is
part of theAB Freight CarAir Brake Equipment with theABDX
Type Control Valve:
1.1.1 ABDX TYPE CONTROL VALVE
The ABDX Type Control Valve controls the flow of air to and
from the brake cylinder and to charge the reservoirs. It consists
of a Pipe Bracket, a Service Portion and an Emergency
Portion.
1.1.2 PIPE BRACKET
TheABDX Control Valve uses the AAR AB type pipe bracket.
This is a two-face pipe bracket to which are mounted the
service and emergency portions. Figures 2 and 3 show the
port identification on each face. The pipe bracket is semi-
permanently bolted to the car. Pipe connections may be made
by means of adjustable welded fittings secured to machined
flange pads on the pipe bracket. No pipe connections need
to be disturbed when removing or replacing the service or
emergency portion. The pipe bracket contains the quick action
chamber and a removable strainer which provides long life by
minimizing the passage of dirt particles to the valve and brake
cylinder.
Pipe Connections - Figure 4 shows the pipe bracket face
to which the pipe connections are made. Each port
connection is identified by number and name.
Figure 1 - Diagrammatic View

Operation & Maintenance Instruction
August, 2003Page 3 of 24
4225-50, S.6
Figure 2 - Pipe Bracket Service Face
Port Identification
Figure 3 - Pipe Bracket Emergency Face
Port Identification
Figure 4 - Pipe Bracket Face Pipe Connections
e3
b
b4
c
c3 c2
Q.A.C.
c4
c3 b2
EX
a
E2
b
Port
a - To Auxillary Reservoir
b - To Brake Pipe
b2 - To Strainer Nut Cavity
c3 - To Emergency Face and Branches c2 and c4
c4 - To Passage c3
e2 - To Emergency Reservoir and to Emergency Face
EX - To Retaining Valve
Port
b - To Brake Pipe
b4 - To Brake Pipe Passage b
c - To Brake Cylinder
c2 - To Passage c3
c3 - To Service Face and Branch Ports c2 and c4
e3 - To Emergency Reservoir and Service Face
Q.A.C. - To Quick Action Chamber
Port Designation Flange Size
1 Brake Pipe 1 inch
2 Emergency Reservoir 3/4inch
3 Brake Cylinder 3/4inch
5 Auxiliary Reservoir 3/4inch
10 Retainer 3/8inch

Operation & Maintenance Instruction
Page 4 of 24
August, 2003
4225-50, S.6
1.1.3 SERVICE PORTION
The Service Portion controls the flow of air from the auxiliary
reservoir to the brake cylinder during a service application
and the recharging of the auxiliary and emergency reservoirs,
and exhaust of brake cylinder during a release. The
accelerated release feature speeds up the recharge of brake
pipe during a release of a service application by the use of a
small amount of air from the emergency reservoir. The Service
Portion also includes a large capacity manual release valve.
This release valve offers the choice of exhausting only the
brake cylinder, exhausting the auxiliary reservoir and brake
cylinder, or exhausting both reservoirs and the brake cylinder.
Figure 2 shows the port identification on the service portion
bolting face. The ABDX-SS Service Portion has been tuned
to optimize the Quick Service function for short cars.
1.1.4 EMERGENCY PORTION
The Emergency Portion controls the flow of air from both
reservoirs to the brake cylinder during an emergency
application. An emergency application can be obtained at
any time regardless of the existing state of service application
or release, provided brake pipe pressure has not been reduced
below 45 psi prior to initiating an emergency. Emergency
brake cylinder air pressure is approximately 20% higher than
that obtained from a full service brake application. The
emergency brake cylinder pressure is developed in two
stages, thus reducing train slack action.
The Emergency Portion also contains the accelerated
application feature which accelerates the service buildup of
brake cylinder pressure throughout the train by locally venting
brake pipe at each car. TheABDX-SS Emergency Portion is
tuned to optimize this feature on short cars with less than 45
feet of brake pipe.
The emergency accelerated release feature speeds up the
recharge of brake pipe during a release of emergency
application by the use of air from the brake cylinder and
auxiliary reservoir.
2.0 OPERATION
Refer to Wabtec Publication 5062-19 for the operation of
ABDX-SS Control Valve.
3.0 MAINTENANCE SCHEDULE
IMPORTANT: The ABDX-SS Control Valve should be
removed from the equipment arrangement, taken to the shop,
be completely disassembled, the parts cleaned, lubricated,
assembled, using NEW Wabtec Corporation rubber parts
and other specified NEW Wabtec Corporation parts. The valve
is then tested according to the following vehicle application
schedule, or more frequently if service conditions so indicate.
RECOMMENDED FREQUENCYAT LEAST
TYPE OF APPLICATION ONCE EVERY
FREIGHT Not to exceed 12 YEARS
4.0 PARTS CATALOG INFORMATION
4.1 PARTS CATALOG
IMPORTANT: When ordering replacement parts for the
ABDX-SS Control Valve, Part No. 664742, or any of its
component portions, refer to the current issue of Wabtec
Corporation Parts Catalog 3225-50, S.6.
NOTE: The reference numbers used in this publication and
those used in the parts catalog may differ. Check the
descriptive parts name to be sure that the desired part is
ordered.
4.2 REPLACEMENT PARTS
IMPORTANT: To obtain satisfactory operation and
reliability of the ABDX-SS Control Valve, ONLY Wabtec
Corporation replacement parts are to be used in the
maintenance of the ABDX-SS Control Valve. Commercially
available parts are unacceptable.
5.0 SAFETY PROCEDURES & WARNINGS
Regular car builder and/or owner-operating property and/or
shop safety procedures MUST BE followed when performing
any work on theABDX-SS Control Valve and/or its component
parts.
The work area should be clean.

Operation & Maintenance Instruction
August, 2003Page 5 of 24
4225-50, S.6
WARNING: The following statements of warning apply,
all or in part, wherever the symbol appears in the
maintenance procedures. Failure to observe these precautions
may result in serious injury to those performing the work
and/or bystanders.
 Portions weigh in excess of 30 pounds. Use care
when lifting and hauling portions to preclude injury.
 Due to the possibility of exhausting air, and high
decibel levels of noise associated with it, from the
device during testing, it is recommended that sufficient
hearing and eye protection be used. This is intended
to minimize the possibilities of hearing and eye injury
to the operator or persons near the test rack.
 The use of an air jet, which must be less than 30
p.s.i.g., to blow parts clean or to blow them dry after
being cleaned with a solvent will cause particles of
dirt and/or droplets of the cleaning solvent to be
airborne. Wire brushing may also cause particles of
dirt, rust and scale to become airborne. These
conditions may cause skin and/or eye irritation.
 When using an air jet, do not direct it toward
another person. Improper use of air jet could result in
bodily injury.
 Personal eye protection must be worn when
performing any work on this device or its component
parts to avoid any possible injury to the eyes.
 The use of solvents and lubricants can involve health
and/or safety hazards. The manufacturers of the solvents
and lubricants should be contacted for safety data (such
as OSHA Form OSHA-20 or its equivalent). The
recommended precautions and procedures of the
manufacturers should be followed.
 When performing any test or work on devices or
equipment while they are on the vehicle (on car test
etc.) special precautions must be taken to ensure that
vehicle movement will not occur which could result in
injury to personnel and/or damage to equipment.
Figure 5 - ABDX-SS Control Valve, Part No. 664742
8
A
B
3
4
5
6
10
9
11
7
C
12
2
1
8

Operation & Maintenance Instruction
Page 6 of 24
August, 2003
4225-50, S.6
 When performing the procedures which follow,
springs within the assembly may be under load.
Exercise care so that no parts are inadvertently expelled.
Inadvertently expelled parts may cause bodily injury,
and/or damage to parts.
 All air supply to this device and/or to any component
part must be cut off and any air in the device be allowed
to vent before this device and/or any component part
is removed from the equipment arrangement.
 Bottled up air under pressure (even though air
supply is cut off) may cause gaskets and/or particles of
dirt to become airborne and an increase in sound level
when this device and/or any component part is removed
from the equipment arrangement. Personal eye and
ear protection must be worn and care taken to avoid
possible injury when performing any work on this device
and/or component part.
 An adequate support or lifting device must be
available to support the device and/or valve portion(s)
during removal, installation and maintenance
procedures.
6.0 CLEANING SOLVENT, LUBRICANT & SEALANT
6.1 CLEANING SOLVENT
6.1.1 The means used to clean the reusable parts of the
ABDX-SS Type Control Valves MUST BE an aliphatic
hydrocarbon solvent, such as mineral spirits or naptha, or a
heated aqueous biodegradable detergent and rinse.
IMPORTANT: Cleaning materials are to be used in a well
ventilated area.
6.2 LUBRICANT
Lubricant Current AAR Specification
Triple Valve Oil M-912
Dry Graphite M-913
Brake Cylinder Lubricant M-914
6.2.1 The o-ring, o-ring grooves and the o-ring bearing
surfaces of the bushing(s) must be lubricated with Number 2
Silicone Grease, Wabtec Corporation Specification M-07680-
02 (Industry Designation MIL-G-4343), such as Dow Corning
Corporation, Dow Corning 55.
6.2.2 The threads of choke plugs and all other removable
plugs, as well as all other threaded parts which may later be
difficult to remove, must be pre-coated with a Loctite product
called Vibraseal #517. The Vibraseal plugs are to be fully
threaded into place, however discretion should be used when
tightening the choke plug, to facilitate removal.
6.3 SEALANT
6.3.1 Locking Sealant, WestinghouseAir Brake Company
Specification M-07499-05, such as Loctite Corporation TL-
242, is required for application to certain threads.
7.0 MAINTENANCE PROCEDURE
7.1 ON-CAR MAINTENANCE PROCEDURES
IMPORTANT: ON-CAR Maintenance is limited to the
removal and replacement of Component Portions. No ON-
CAR repair of the valve is to be attempted.
7.1.2 SPECIAL TOOLS
IMPORTANT: The information shown in Figures 6 thru 11,
for making tools, is furnished as a convenience. The Wabtec
Corporation shall have NO responsibility for tools which they
do not manufacture and will not be responsible for the results
when using any of the specified tools (including claims by
third parties).
7.2 PORTION REMOVAL & INSTALLATION - "ON CAR"
7.2.1 IMPORTANT: ALL car builder and owner-
operating property safety procedures, in addition to warnings
as listed in Section 5 of this publication, MUST BE adhered to.
7.2.2 IMPORTANT: The handbrake(s) of the car
MUST BE applied and the wheels of the car chocked to
prevent unintentional car movement. Warning placards
indicating that work is being performed are to be placed on
and about the car.
7.2.3 IMPORTANT: ALL air flow to the ABDX-SS
Control Valve MUST BE allowed to deplete and subsequently
be cut off.

Operation & Maintenance Instruction
August, 2003Page 7 of 24
4225-50, S.6
Figure 8 - Service Piston Assembly Fixture
Figure 6 - Hand Tool for Diaphragm Installation Figure 7 - Mandrel for Installing O-rings
Piston or Spool Valve
O-rings
Mandrel
Air Hole

Graduating Valve Spring
Driver
Roll Pin
Section A-A
Slide Valve Spring
Slide Valve
Graduating Valve
Piston Stem
Slide Valve Spring
Fixture Back Plate
Jaws of Bench Vise
Fixture Body
Roll Pin in Place
A
Graduating Valve
Fixture Back Plate
A


1/4R
3/4
3/4
3/32
Approx. 8
1











Material: Steel
Break Corners and Remove Burrs



Operation & Maintenance Instruction
Page 8 of 24
August, 2003
4225-50, S.6
Figure 9 - Limiting Valve Piston Spanner Wrench Figure 10 - Service Accelerated Release Valve
Piston Spanner Wrench
No. 23
(0.154) Drill (2
Holes)
9/64 Deep
Break Corners
and
Remove Burrs
23/4
21/85/16
7/8
41/4
3/8
1
13/8
23/4







 







5/32 x 9/32
Steel Dowel
Pin (2 Reqd)
Press in Place

Material: Steel
To Be Manufactured
By Customer
Figure 11 - Inshot Piston Spanner Wrench
11/4
7/167/16
5/8
1/4
No. 43
(0.089) Drill
(2 Holes)
25/64 Drill
3/32 x 5/16
Steel Dowel Pin (2
Reqd)
Press in Place
5
Material: Steel
Break Corners and Remove Burrs To Be Manufactured By Customer
5/8














5/16
1/8 x 3/8
Steel Dowel Pin
(2 Reqd)
Press in Place
Material: Steel
Break Corners and Remove Burrs
7/16 Drill
0.120 Drill
(2 Holes)
31/6431/64
3/4
11/2
6
To Be Manufactured By Customer
3/4













Operation & Maintenance Instruction
August, 2003Page 9 of 24
4225-50, S.6
7.2.4 Emergency Portion Removal and Installation
See Figure 5
7.2.4.1 Scrape, wipe and blow off with a jet of low
pressure air (less than 30 psi) all dirt adjacent to the gasket
between the pipe bracket and emergency valve portion. Using
the blower hose, blow off the emergency portion, pipe bracket
hopper slopes, car under frames, etc., to free them of all
loose dirt that may otherwise get into the emergency portion
or pipe bracket when the portion is being removed and
reapplied.
7.2.4.2 Remove the vent protector from the failed emergency
portion and apply a WABCO Freight Car Products standard
vent protector plug, as shown in Figure 17.
7.2.4.3 The cleaned emergency portion must be handled
with care to avoid entrance of dirt or water which could
damage the internal parts.
IMPORTANT: The shipping cover must not be removed
from the clean replacement emergency portion until it is ready
to be mounted to the pipe bracket on the car.
7.2.4.4 Remove the Emergency Portion (1) from the Pipe
Bracket Portion (7) by first removing the three 5/8 hex nuts
(8) and apply a shipping cover, as shown in Figure 15, and
tighten nuts.
7.2.4.5 Remove and SCRAP the Emergency Portion
Mounting Gasket (2) from the mounting face of the Pipe
Bracket (7).
7.2.4.6 Visually inspect the Pipe Bracket Portion (7) for
damage. This portion need not be removed from the
equipment arrangement unless it is damaged. If it is
necessary to remove the Pipe Bracket Portion (7), car builder
and owner-operating property instructions are to be followed.
7.2.4.7 Inspect the Emergency Portion mounting face of the
Pipe Bracket Portion (7) to be sure that it is clean and is not
damaged or scratched. Be sure that ALL parts are clean
and unrestricted. If necessary, the ports can be blown out
with a low pressure jet of clean dry air. Exercise care so that
no dirt is blown into the ports or passages of the Pipe Bracket
Portion (7).
7.2.4.8 Apply a NEW WABCO Freight Car Products
Emergency Portion Mounting Gasket (2) to the Pipe
Bracket (7).
7.2.4.9 Remove the Vent Protector Plug from the new or
satisfactorily repaired and tested Emergency Portion (1).
Install a cleaned or renewed Vent Protector into the new
Emergency Portion (1).
WARNING: TheABDX-SS portions must not be applied
to cars exceeding 39 feet in length. Such incorrect application
may result in undesired brake action that could cause
equipment damage and injury to bystanders.
7.2.4.10 Remove the shipping cover from the new or
satisfactorily repaired and tested Emergency Portion (1) and
immediately apply the Emergency Portion (1) to the Pipe
Bracket (7). Coat the threads of the mounting studs lightly
with brake cylinder lubricant (M-914) or a compound
consisting of one part graphite, Wabtec Specification [M-
07695-02] (AAR Specification M-913), and two parts oil (SAE-
20) by weight.
7.2.4.11 Tighten the three5 /8  hex nuts (8) evenly and firmly
in order to sufficiently prevent gasket leakage and yet not
excessively to cause distortion of the mounting gasket (2).
7.2.4.12 After the Emergency Portion (1) has been
reinstalled and all repairs have been completed, the entire
air brake equipment must be tested in accordance with the
latest issue of the Code of Air Brake System Tests for Freight
Equipment T-664742A/B-O.
7.2.5 Service Portion Removal and Installation
See Figure 5
7.2.5.1 Disconnect the release valve handle or handles,
leaving it attached to the release rod or rods.
7.2.5.2 Scrape, wipe and blow off with a jet of low
pressure air (less than 30 psi) all dirt adjacent to the gasket
between the Pipe Bracket (7) and Service Portion (3). Using
the blower hose, blow off the Service Portion (3), Pipe Bracket
(7), hopper slopes, car underframe, etc., to free them of all
loose dirt that may otherwise get into the Service Portion or
Pipe Bracket when the portion is being removed and
reapplied.
7.2.5.3 The cleaned Service Portion (3) must be handled
with care to avoid entrance of dirt or water which could damage
the internal parts.

Operation & Maintenance Instruction
Page 10 of 24
August, 2003
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7.2.5.4 IMPORTANT: The shipping cover must not be
removed from the clean replacement Service Portion until it
is ready to be mounted to the Pipe Bracket on the car.
7.2.5.5 Remove the failed Service Portion (3) and apply the
shipping cover and tighten nuts.
7.2.5.6 Apply standard or alternate stem guard (See Figure
16) to the removed Service Portion and hold in place with
cotter pin.
7.2.5.7 Remove Service Portion Mounting Gasket (4) and
discard properly.
7.2.5.8 Remove the strainer nut (5) using strainer nut wrench
then remove and discard the old air strainer (6).
7.2.5.9 Install a NEW air strainer (6). A wooden mandrel of
suitable form will assist in guiding the strainer into proper
position. Make certain its inner end is in engagement with
the sealing bead (if inserted properly, all nut threads will be
visible), then insert strainer nut (5) and tighten it firmly using
the strainer nut wrench.
7.2.5.10 Install a NEW Service Portion Mounting
Gasket (4).
WARNING: TheABDX-SS portions must not be applied
to cars exceeding 39 feet in length. Such incorrect application
may result in undesired brake action that could cause
equipment damage and injury to bystanders.
7.2.5.11 Remove the shipping cover from the new or
satisfactorily repaired and tested Service Portion (3) and
immediately apply the portion to the Pipe Bracket (7). Coat
the threads of the mounting studs lightly with brake cylinder
lubricant (M-914) or a compound consisting of one part
graphite, Wabtec Specification M-07695-02 (AAR
Specification M-913), and two parts oil (SAE-20) by weight.
7.2.5.12 Tighten the three 5/8 hex nuts (8) evenly and
firmly in order to sufficiently prevent gasket leakage and yet
not excessively to cause distortion of Mounting Gasket (4).
7.2.5.13 Remove release valve stem guard from the new
or repaired service portion and reconnect the release valve
handle or handles (which has been left attached to release
rod) to release valve handle end plate with a new cotter pin.
7.2.5.14 After the Service Portion has been reinstalled
and all repairs have been completed, the entire air brake
equipment must be tested in accordance with the latest issue
of the Code ofAir Brake System Tests for Freight Equipment
T-664742A/B-O.
7.3 "IN-SHOP" MAINTENANCE PROCEDURES
IMPORTANT: The procedures which follow are to be
performed in the repair shop. To obtain satisfactory operation
and reliability of this device only replacement parts supplied
by Wabtec Corporation are to be used in the maintenance of
this device.
IMPORTANT: When performing the procedures which
follow, DO NOT use hard or sharp metal tools to remove
gaskets, o-rings, the dust boot, or diaphragm. Exercise care
so that no damage is done to parts.
WARNING: When performing the procedures which
follow, springs within the assembly may be under load.
Exercise care so that no parts are inadvertently expelled.
Inadvertently expelled parts may cause bodily injury, and/or
damage to parts.
7.4 DISASSEMBLY ofABDX-SS EMERGENCY PORTION
See Figure 12
7.4.1 Remove the vent protector assembly from the
emergency portion body (58) if it is still in place. The vent
protector assembly is not illustrated in Figure 12.
7.4.2 Small Vent Valve Piston, Inshot Check Valve
7.4.3 Depress the spring retainer (28) into the body (58)
and tilt it so that it is free of the retaining lip in the body
(58) and remove the retainer (28), vent valve spring (29),
and the small vent valve (23) from the body (58).
7.4.4 Depress the spring retainer (25) into the body (58)
and tilt it so that it is free of the retaining lip in the body (58)
and remove the retainer (25), inshot check valve spring (26),
and the check valve (27) from the body (58). SCRAP the
check valve (27).
7.4.5 Emergency Diaphragm Piston, High Pressure Spool,
Emergency Accelerated Release Check Valve

Operation & Maintenance Instruction
August, 2003Page 11 of 24
4225-50, S.6
Figure 12 - ABDX-SS Aluminum Emergency Portion
1
3
4
5
10
11
27
7
6
89
12
28
29
24
25
26
57
55&56
54
54
48
49
58
46
47
45
43
44
42
41
40
39
38
37
32
30
31
34
33
35
54
51, 52
&53
36
59, 60
&61
14
16
15
13
20 21
19
18
17
23
22
23
2
50
62

Operation & Maintenance Instruction
Page 12 of 24
August, 2003
4225-50, S.6
7.4.6 Remove the four 1/2" x 13/4" hex head screws (1)
which secure the top cover (2) to the body (58). Remove the
cover (2).
7.4.7 Remove and SCRAP the ring gaskets (22, 23, 24)
from the top cover (2).
NOTE: The thimble type air strainer (21) can be removed by
first removing the retaining ring (20) from the body (58).
7.4.8 Remove the emergency accelerated release check
valve spring (17), check valve spring seat (18), emergency
accelerated release check valve (19), retaining ring (20), and
the thimble type air strainer (21) from the body (58). SCRAP
the check valve (19).
7.4.9 Remove the high pressure spool valve return spring
(13) and the high pressure spool valve with o-rings (16, 15)
from the body (58).
NOTE: For easier removal, thread a 3/8-16 cap screw into
the high pressure spool.
7.4.10 Remove and SCRAP the five 13/16" O.D. o-rings (15)
from the high pressure valve (16).
7.4.11 Carefully remove the emergency diaphragm piston
assembly (3 to 12) as a unit from the body (58).
7.4.12 Carefully drift the 3/32" x 3/4" cylindrical spring pin (6)
from the emergency slide valve (8). Remove the emergency
slide valve (8), filter (9), and spring (7) from the emergency
piston (10).
7.4.13 Remove the 5/8" x 1" hex head cap screw (3) that
secures the diaphragm follower (4) and diaphragm (5) to the
emergency piston (10). Remove follower (4) and diaphragm
(5) from the piston (10). SCRAP the diaphragm (5).
7.4.14 Remove and SCRAP the two emergency wear rings
(11 and 12) from the emergency piston (10).
7.4.15 Vent Valve, Inshot Piston, Emergency Accelerated
Release Spool
7.4.16 Remove the two 1/2 x 11/8 hex head cap screws (31)
and the 1/2 x 13/4 hex head cap screw (32) that secures the
vent valve cover (33) to the body (58).
7.4.17 Remove the inshot piston spring (38) and the inshot
piston assembly (39 to 43) from the body (58).
7.4.18 Remove and SCRAP the 15/16" O.D. ring gasket (34)
and the 5/8" O.D. ring gasket (35) from the vent valve cover
(33).
7.4.19 Remove and SCRAP the 3/8" O.D. o-ring (40) from
the inshot piston (41).
7.4.20 Use the inshot piston spanner wrench, as shown in
Figure 9, to hold the inshot piston (43), then remove the 3/8"
self-locking hex nut (39) from the piston (43). SCRAP the
nut (39).
7.4.21 Remove the diaphragm follower (40) and diaphragm
(41) from the piston (43). SCRAP the diaphragm (41).
7.4.22 Remove the vent valve piston diaphragm (36) and
the vent valve piston (37) from the body (58). SCRAP the
diaphragm (36).
WARNING: The cap nut (45) is under spring load.
Exercise care so that no parts are inadvertently expelled
from the assembly. Inadvertently expelled parts may cause
bodily injury.
7.4.23 Using a 7/8" square wrench, remove the cap nut with
o-ring (45, 44), which secures the emergency accelerated
release spool valve spring (46) and emergency accelerated
release spool valve (48) with o-rings (47) in the body (58).
7.4.24 Remove the emergency accelerated release spool
valve spring (46) and emergency accelerated release spool
valve (48) with o-rings (47) from the bottom of the body (56).
7.4.25 Remove and SCRAP the four 11/2" O.D. o-rings (47)
from the spool valve (48).
7.4.26 Remove and SCRAP the 11/2" O.D. o-ring (44) from
the cap nut (45).
7.5 ASSEMBLY of ABDX-SS EMERGENCY PORTION
See Figure 12
7.5.1 Emergency Diaphragm Piston, High Pressure Spool,
Emergency Accelerated Release Check Valve

Operation & Maintenance Instruction
August, 2003Page 13 of 24
4225-50, S.6
7.5.2 Using #2 Silicone Grease, Wabtec Corporation
Specification M-07680-02, coat the surfaces of four NEW
11/2" O.D. o-rings (47). Also, lightly lubricate the o-ring grooves
of the emergency accelerated release spool valve (48) and
the spool valve bushing surfaces of the body (58).
7.5.3 Install the four NEW, lubricated 11/2" O.D. o-rings
(47) into their grooves on the emergency accelerated release
spool valve (48).
7.5.4 Install the emergency accelerated release spool
valve (48) with o-rings (47) into its bush in the body (58),
closed end first.
7.5.5 Install the emergency accelerated release spool
valve spring (46) into the spool valve (48).
7.5.6 Apply #2 Silicone Grease, Wabtec Corporation
Specification M-07680-02, to the surfaces of a NEW 11/2"
O.D. o-ring (44) and lightly lubricate the o-ring groove of the
cap nut (45).
7.5.7 Install the NEW lubricated 11/2" O.D. o-ring (44) into
its groove on the cap nut (45).
7.5.8 Install the cap nut with o-ring (45 & 44) into the body
(58) to secure the spring (46) and accelerated release spool
valve (48) with o-rings (47) in place. Using a 7/8" square wrench,
tighten the cap nut (45) between 55 and 65 foot-pounds of
torque.
7.5.9 Install the emergency wear rings (11 & 12) on the
emergency piston (10).
IMPORTANT: Care should be taken when expanding or
opening the wear rings during installation onto the emergency
piston. Do not overexpand the rings causing them to deform
which would result in difficult installation of the piston into
the bore. The protective ring should be installed with the gap
facing the slide valve area of the emergency piston. The
positioning of the rings will ease the assembly.
7.5.10 Install a NEW emergency piston diaphragm (5) on
the emergency piston (10) so that the piece number on the
diaphragm is facing away from the piston.
7.5.11 Lightly coat the threads of the 5/8" x 1" hex head
screw (3) with LOCTITE Sealant TL-242, Wabtec Corporation
Specification M-07499-05. Install the cap screw (3) through
the diaphragm follower (4) and into the piston (10) to secure
the piston (10), diaphragm (5) and follower (4) together. Hand
tighten the cap screw (3) and flip the diaphragm (5) in the
opposite direction so that the large cone shaped opening is
facing the piston (10). Torque the screw (3) between 45 and
50 foot-pounds.
7.5.12 Insert the emergency slide valve spring (7) into the
emergency slide valve (8).
7.5.13 Carefully place the emergency slide valve with spring
(8 & 7) on the stem of the piston (10) and secure the parts in
place by installing the 3/32" x 3/4" cylindrical spring pin (6).
7.5.14 Using a foam-tipped applicator, evenly spread a light
coating of Triple Valve Oil, Wabtec Corporation Specification
M-07611-20, (AAR Specification M-912) over the face of the
emergency slide valve (8).
7.5.15 Evenly spread a light coating of the Triple Valve Oil
on the slide valve bushing seat of the body (58).
7.5.16 Evenly spread a light coating of Triple Valve Oil over
the guide portion of the stem and piston end of the piston (10).
IMPORTANT: Care must be taken when compressing the
slide valve spring (7) in preparation for inserting the emergency
piston assembly (3 to 10) into the body bushing. While using
minimal force, the assembly must be aligned squarely to
prevent any wedging or distortion. The slide valve face (8)
must be retracted from the bushing face as long as possible.
7.5.17 Install the diaphragm - piston - emergency slide valve
assembly (3 to 10) into the body (58). Exercise care so that
NO damage is done to the emergency slide valve bushing
seat.
7.5.18 Using the pressure of the thumb or finger, position
the sealing bead of the diaphragm in the diaphragm bead
groove of the body (58).
7.5.19 Coat the surfaces of five NEW 13/16" O.D. o-rings
(15) with #2 Silicone Grease, Wabtec Corporation
Specification M-07680-02. Also lightly lubricate the o-ring
grooves of the high pressure spool valve (16) and the bearing
surfaces of the spool valve bushing of the body (58).
7.5.20 Install the five NEW lubricated 13/16" O.D. o-rings
(15) into their grooves on the high pressure spool valve (16).

Operation & Maintenance Instruction
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August, 2003
4225-50, S.6
7.5.21 Install the high pressure spool valve with o-rings (16,
15) into the body (58).
7.5.22 Install the high pressure spool valve return spring
(13) into the high pressure spool valve (16).
7.5.23 Install a NEW thimble type air strainer (21) into the
emergency accelerated check valve seat of the body (58).
Secure the thimble type air strainer (21) into the body (58)
with the retaining ring (20).
7.5.24 Install a NEW emergency accelerated release check
valve (19) and check valve spring seat (18) and the check
valve spring (17) into the body (58).
7.5.25 Install a NEW 13/4" O.D. ring gasket (22), two NEW
11/2" O.D. ring gaskets (23) and a NEW 11/8" O.D. ring gasket
(24) into their grooves in the top cover (2).
7.5.26 Place the top cover assembly (2) with ring gaskets
(22, 23, 24) on the body (58) making sure that the diaphragm
(5) and ring gaskets (22, 23, 24) remain in position.
7.5.27 Secure the cover (2) to the body (58) by installing
the four 1/2" x 13/4" hex head screws (1). Torque the screws
between 35 and 55 foot-pounds.
7.5.28 Vent Valve, Inshot Piston, Emergency Accelerated
Release Spool
7.5.29 Install a NEW inshot diaphragm (41) on the inshot
piston (43) so that the flat surface of the diaphragm which
shows the part number faces away from the piston.
7.5.30 Install the diaphragm follower (40) on the piston (43)
so that the small diameter of the follower (40) is facing the
diaphragm (41). Secure the follower (40) and the diaphragm
(41) on the inshot piston (43) by installing a NEW 3/8-16 self-
locking hex nut (39). Torque the nut to 9 to 12 foot-pounds.
7.5.31 Apply #2 Silicone Grease, Wabtec Corporation
Specification M-07680-02, to the surfaces of a NEW 3/8" O.D.
o-ring (42). Also lightly lubricate the O-ring groove on the
shaft of the inshot piston (43) and the bearing surfaces of the
inshot piston bushing of the body (58).
7.5.32 Install the NEW lubricated 3/8" O.D. o-ring (42) into
its groove on the shaft of the inshot piston (43).
7.5.33 Install the inshot diaphragm piston assembly (39 to
43) into the body (58). Be sure that the bead of the diaphragm
(41) is properly seated in the bead groove of the body (58).
7.5.34 Install the inshot piston spring (38) over the nut (39)
on the exposed end of the inshot piston (43) so that the
spring seats in the diaphragm follower (40).
7.5.35 Using a foam-tipped swab applicator, evenly
spread a light coating of Triple Valve Oil, Wabtec
Corporation Specification M-07611-20 (AAR Specification
M-912), to the large diameter surface of the stem of the
vent valve piston (37). Carefully insert the vent valve piston
(37) into the body (58).
7.5.36 Place a NEW vent valve piston diaphragm (36) on
the vent valve piston (37) ensuring that the part number on
the diaphragm faces the piston. With the aid of the hand
tool, shown in Figure 6, properly position the diaphragm
(36) so that the loop of the diaphragm sits between the piston
(37) and body (58).
7.5.37 Install a NEW 15/16" O.D. ring gasket (34) and a NEW
5/8" O.D. ring gasket (35) in their grooves in the vent valve
cover (33).
7.5.38 Place the vent valve cover (33) on the body (58) and
install the two 1/2 x 11/8 hex head screws (31), the METAL
IDENTIFICATION TAG (29a), and the 1/2 x 13/4 hex head
cap screw (32).
7.5.39 Small Vent Valve, Inshot Check Valve
7.5.40 Install a NEW inshot check valve (27) and the inshot
check valve spring (26) into the body (58).Align properly and
secure these parts in place by installing the inshot spring
retainer (25).
7.5.41 Using a foam-tipped swab applicator, evenly spread
a light coating of Triple Valve Oil, Wabtec Corporation
Specification M-07611-20 (AAR Specification M-912), to the
outer diameter surfaces of the small vent valve piston (30).
Install the small vent valve piston assembly (30) seal end
first, into the body (58).
7.5.42 Install the small vent valve piston spring (29) into the
small vent valve (30) and secure it in place by installing the
spring retainer (28) in the body (58). Be sure that the retainer
(28) is properly secured.

Operation & Maintenance Instruction
August, 2003Page 15 of 24
4225-50, S.6
Figure 13 - ABDX-SS Service Portion, Part No. 664743
1
2
34
5
6
7
8
9
10
11
12
13
14
15
16
17
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34 35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
53
55
56
57
54
52

Operation & Maintenance Instruction
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August, 2003
4225-50, S.6
7.6 DISASSEMBLY of ABDX-SS SERVICE PORTION
See Figures 13 & 14
7.6.1 Remove the release valve portion (54) from the body
(49) by first removing the three 3/8" flanged hex nuts (52).
7.6.2 Remove and SCRAP the five 13/16" O.D. ring gaskets
(56) and the 7/8" O.D. ring gasket (55) from the mounting face
of the release valve portion (54). Remove the wire mesh
strainers (57) from the body (49).
7.6.3 Set the release valve portion (54) aside in a clean,
protected area for later disassembly.
7.6.4 Service Diaphragm Piston
7.6.5 Remove the top cover (2) from the body (49) by
removing the four 1/2" x 13/4" hex head screws (1).
7.6.6 Remove and SCRAP the 11/16" O.D. ring gasket (3)
from the top cover (2).
7.6.7 Carefully remove the service piston assembly
(4to17) as a unit from the body (49).
7.6.8 Place the service piston assembly (4to17) on the
Service Piston Assembly fixture, Part No. 564522 as shown
in Figure 8. Hold the service piston assembly in position so
that the slide valve spring (13) rests on the fixture with the
seat of the slide valve (15) facing upward.
7.6.9 Using the driver pin that is furnished with the piston
holding fixture, carefully drift the 3/32" x 1" cylindrical spring
pin (11) from the slide valve (15).
7.6.10 Remove the slide valve spring (12), slide valve (15),
graduating valve (14) and graduating valve spring (13) from
the service piston (16).
7.6.11 Remove the 5/8" x 1" hex head cap screw (4) which
secures the diaphragm follower (5) and diaphragm (6) to the
service piston (17).
7.6.12 Remove the diaphragm follower (5) and diaphragm
(6) from the service piston (16). SCRAP the diaphragm (6).
7.6.13 Remove the spring seat retaining ring (7) from the
tail of the service piston (16), then remove the spring seat
(8), spring (9) and spring guide (10). Remove and SCRAP
the service piston rings (17) from the service piston (16).
7.6.14 Limiting Valve, Back Flow Check Valve
7.6.15 Remove the four 1/2" x 11/4" hex head screws (33)
which secure the bottom cover (44) to the body (49).
WARNING: The bottom cover (44) is under spring load.
Exercise care so that no parts are inadvertently expelled
from the assembly. Inadvertently expelled parts may cause
bodily injury.
7.6.16 Remove the bottom cover (34) from the body (49).
7.6.17 Remove and SCRAP the 11 /16" O.D. ring gasket (38),
the 2" O.D. ring gasket (35) and the 2" flange fitting gasket
(39) from the cover (34).
7.6.18 Remove the check valve spring (36) and the check
valve (37) from the body (49). SCRAP the check valve (37).
7.6.19 Remove the brake cylinder limiting valve spring (42),
diaphragm follower (43) and the brake cylinder limiting valve
diaphragm (44) from the body (49).
7.6.20 Remove and SCRAP the o-rings (46 & 47) from the
brake cylinder limiting valve stem (45).
7.6.21 Remove the piston return spring (40) and the spring
cage (41) from the body (49).
7.6.22 Accelerated Service Release Valve
7.6.23 Remove the service accelerated release valve cover
(19), wear protection disk (20), and diaphragm/piston
assembly (21 to 24) as a unit from the filling piece (31) by
first removing the four 1/2" x 23/4" hex head screws (18).
7.6.24 Remove the service accelerated release valve piston/
diaphragm assembly (21to24) from the cover (19).
7.6.25 Using the ServiceAccelerated Release Valve Piston
Spanner Wrench, as shown in Figure 10, to hold the service
accelerated release valve piston (24), remove the 9/16" hex
head nut (21), diaphragm follower (22) and the diaphragm
(23) from the threaded end of the piston (24). SCRAP the
diaphragm (23).
NOTE: If required, use a flat bar placed in the slot to retain
the service accelerated release piston (24) while removing
the 9/16 hex head nut (21).

Operation & Maintenance Instruction
August, 2003Page 17 of 24
4225-50, S.6
Figure 14 - ABDX Release Valve Portion, Part No. 566198
35
1
2
4
5
6
3
7
8
9
10
12
11
13
14
17
23
26
21
22 20
19 16
18
27
34
28
30
31
15
32
33
25
24
29

Operation & Maintenance Instruction
Page 18 of 24
August, 2003
4225-50, S.6
7.6.26 Remove the service portion filling piece, plunger,
check valve assembly, and mounting gasket (25 to 32) as a
unit from the body (49).
7.6.75 Remove and SCRAP the filling piece mounting
gasket (32).
7.6.28 Compress and remove the spring seat (28), check
valve spring (29), and accelerated release check valve (30)
from the filling piece (31). SCRAP the check valve (30).
7.6.29 Remove the service accelerated release valve plunger
with o-ring (25, 26) by pushing it out of the cover end of the
filling piece (31). Remove and SCRAP the 1/4" O.D. o-ring
(26) from the end of the plunger (25).
7.6.30 Remove and SCRAP the 11/16" O.D. ring gasket (27)
from its groove in the filling piece.
7.6.31 Retrieve the release valve portion (54) which was
previously set aside in a clean, protected area.
7.6.32 Disassembly of Release Valve Portion
See Figure 14
7.6.33 Remove the five 3/8" x 11/2" hex head screws (1) which
secure the top cover (2) of the release valve portion to the
release valve body (35).
7.6.34 Remove the top cover (2) from the body (35).
7.6.35 Remove and SCRAP the two 1" O.D. ring gaskets
(3) from their grooves in the top cover (2).
7.6.36 Remove the two check valve springs (12), the
auxiliary and emergency reservoir check valves (13) and the
two check valve plungers (14) from the body (35). SCRAP
the two check valves (13).
7.6.37 Remove the spool valve spring (4) from the body (35).
7.6.38 Remove the spool valve - diaphragm follower -
diaphragm assembly (5 to 11) from the body (35) as a unit.
7.6.39 Remove and SCRAP the three 3/4" O.D. o-rings (11)
from their grooves on the spool valve (10).
7.6.40 Using an open end wrench to hold the spool valve
(10), remove the 3/8" self-locking nut (5), diaphragm follower
(6), diaphragm (7) and the piston with o-ring (8, 9) from
the threaded end of the spool valve (10). Remove the 1/2"
O.D. o-ring (9) from its groove in the piston (8). SCRAP
the o-ring (9), diaphragm (7) and the self-locking nut (5).
7.6.41 Remove and SCRAP the 3/16" x 2" cotter pin (24)
which secures the release valve stem guard (25) to the stem
and end plate (27). Remove the stem guard (25).
WARNING: The bottom cover (31) is under spring load.
Exercise care so that no parts are inadvertently expelled
from the assembly. Accidently expelled parts may cause
bodily injury.
7.6.42 Remove the five 3/8" x 13/4" hex head cap screws
(15) that secure the bottom cover, valve seal, exhaust seal
stem, and end plate assembly (27 to 33) to the body (35).
Remove the cover assembly from the body (35).
7.6.43 Remove the stem and end plate (27), bottom cover
gasket (28), seal (30) and 5/8" O.D. ring gasket (29) from the
cover (31). SCRAP the gaskets (28, 29) and seal (30).
7.6.44 Remove the lifter (26) and lifter spring (23) from the
body (35).
7.6.45 Remove the bottom cover sleeve (34) from the bottom
cover (31).
7.6.46 Cut off the head of the 3/16" x 1/2" aluminum pop rivet
(33) and remove the rivet (33) and seal (32) from the bottom
cover (31). SCRAP the rivet (33) and seal (32).
7.6.47 Remove the retaining check valve (20) and its spring
(19) from the body (35). SCRAP the check valve (20).
7.6.48 Remove the reset check valve spring (22) and the
reset check valve (21) from the body (35). SCRAP the check
valve (21).
7.6.49 Remove the reset spool valve with o-ring assembly
(18, 17) and the reset spool valve spring (16) from the
body (35).
7.6.50 Remove and SCRAP the three 3/4" O.D. o-rings (17)
from the reset spool valve (18).

Operation & Maintenance Instruction
August, 2003Page 19 of 24
4225-50, S.6
7.7 ASSEMBLY of ABDX-SS SERVICE PORTION
See Figure 13
7.7.1 Service Diaphragm Piston
7.7.2 Install the service piston rings (17) on the service
piston (16).
IMPORTANT: Care should be taken when expanding or
opening the service piston rings during installation onto the
service piston. Do not overexpand the rings causing them to
deform which would result in difficult installation of the piston
into the bore. The service piston ring should be installed with
the gap facing the slide valve area of the service piston. The
positioning of the rings will ease the assembly.
7.7.3 Position a NEW diaphragm (6) on the service piston
(16) so that the part number on the diaphragm (6) faces away
from the piston (16). After positioning the diaphragm bead
into the groove of the piston, flip the diaphragm (6) so that
the large cone shaped opening is facing the follower (5).
7.7.4 Position the diaphragm follower (5) on the diaphragm
(6) and piston (16).
7.7.5 Lightly coat the threads of the 5/8" x 1" hex head cap
screw (4) with Loctite Sealant TL-242, Wabtec Corporation
Specification M-07499-05. Install the cap screw (4) through
the diaphragm follower (5) and into the piston (16) to secure
the piston (16), diaphragm (6) and follower (5) together. Hand
tighten the cap screw (4) and flip the diaphragm (6) in the
opposite direction so that the large cone shaped opening is
facing the piston (16). Torque the screw (4) between 45 and
50 foot-pounds.
7.7.6 Using a foam-tipped swab applicator, evenly spread
a light coating of Triple Valve Oil, Wabtec Corporation
Specification M-07611-20 (AAR Specification M-912) around
the surfaces of the piston spring guide (10) and the bearing
surfaces of the piston bushing.
7.7.7 Install the piston spring guide (10), closed end first,
into the open end of the service piston (16).
7.7.8 Install the piston spring (9) and spring seat (8) into
the open end of the spring guide (10) and secure the parts in
place by installing the spring retainer (7).
7.7.9 Place the slide valve spring (12) on the holding fixture,
Part No. 564522, as shown in Figure 8.
7.7.10 Using a foam-tipped swab applicator, evenly
spread a light coating of Triple Valve Oil, Wabtec
Corporation Specification M-07611-20, (AAR Specification
M-912) on the face of the graduating valve (14) and over
the graduating valve seat of the slide valve (15).
7.7.11 Install the graduating valve spring (13), graduating
valve (14), and slide valve (15) on to the piston (16).
7.7.12 Place the piston assembly on the slide valve spring
(12) which is still in the holding fixture.
7.7.13 Make sure that the graduating valve (14) is on its
seat in the slide valve (15) and that the slide valve side wings
are down tight in the fixture.
7.7.14 Install the 3/32" x 1" cylindrical spring pin (11) through
the pin holes of each of the wings of the slide valve (15) and
the aligned pin hole of the slide valve spring (13). With the
aid of the pin driver supplied with the holding fixture, Part No.
564522, secure the pin (11) in place.
7.7.15 Remove the assembly from the holding fixture.
7.7.16 Using a foam-tipped swab applicator, evenly spread
a light coating of Triple Valve Oil, Wabtec Corporation
Specification M-07611-20 (AAR Specification M-912) over the
face of the slide valve (15) and the service piston rings (17)
on the service piston (16). Also apply a light coating of the
Triple Valve Oil to the slide valve seat of its bushing in the
body (49), and to the collars and fins of the piston (16) near
the piston head.
IMPORTANT: Care must be taken when compressing the
graduating valve and slide valve in preparation for inserting
the service piston assembly with rings (4 to 17) into the body
bushing. While using minimal force, the assembly must be
aligned squarely to prevent any wedging or distortion. The
slide valve face (15) must be retracted from the bushing face
as long as possible. Care must be taken not to damage the
slide valve seats.
7.7.17 Install the piston - diaphragm - slide valve assembly
(4 to 17) into the body (49) from the top, exercising care so
that NO damage is done to the slide valve seat.

Operation & Maintenance Instruction
Page 20 of 24
August, 2003
4225-50, S.6
7.7.18 Using only finger and thumb pressure, position the
sealing bead of the diaphragm (6) into the diaphragm bead
groove on the top cover mounting face of the body (49).
7.7.19 Install a NEW 11/16" O.D. ring gasket (3) into its
groove in the top cover (2).
7.7.20 Insert two guide pins into two diagonally opposite
threaded holes of the body (49). Using the pins as guides,
position the cover assembly (2, 3) onto the body (49). In the
remaining two threaded holes, tighten by hand, two 1/2" x 13/4"
hex head cap screws (1). Remove the two guide pins and
install the other two 1/2" x 13/4" hex head cap screws (1). Torque
all four cap screws between 35 and 55 foot-pounds.
7.7.21 Limiting Valve, Back Flow Check Valve
7.7.22 Using a foam-tipped swab applicator, evenly spread
a light coating of Triple Valve Oil, Wabtec Corporation
Specification M-07611-20 (AAR Specification M-912) around
the collar on each end of the spring cage (41).
7.7.23 Install the piston return spring (40) into the spring
cage (41), then install the cage with spring (41,40) as a unit
into the body (49) so that the spring (40) goes over and around
the end of the shaft of the piston (16), which has already
been installed.
7.7.24 Position a NEW diaphragm (44) onto the brake
cylinder limiting valve stem (45) so that the flat surface of the
diaphragm, which shows the part number, faces away from
the stem towards the threaded end.
7.7.25 Using #2 Silicone Grease, Wabtec Corporation
Specification M-07680-02, lubricate the surfaces of two NEW
o-rings (47, 46). Also lightly lubricate the o-ring grooves on
the shaft of the stem (45) and the bearing surfaces of the
piston bushing in the body (49).
7.7.26 Install the spring, stem and diaphragm (45 to 48)
into the body (49), o-ring end first. Be sure that the bead of
the diaphragm (44) is properly seated in its groove in the
body (49). Use finger pressure to seat the bead.
7.7.27 Install the diaphragm follower (43) and brake cylinder
limiting valve spring (42) into the body (49) so that it seats on
the diaphragm follower (44).
7.7.28 Install a NEW back flow check valve (37) and
the check valve spring (36) into the proper cavity of the
body (49).
7.7.29 Install a NEW 2" flange fitting gasket (39), a NEW
2" O.D. ring gasket (35) and a NEW 11/16" O.D. ring gasket
(38) into their grooves in the bottom cover (34).
7.7.30 Carefully position the bottom cover assembly (34,
35, 38 and 39) on the body (49) making sure that all gaskets
and assemblies of the body are properly in place. Secure
the bottom cover (34) to the body (49) by installing four 1/2" x
11/4" hex head screws (33). Equally torque the screws
between 35 and 55 foot-pounds.
7.7.31 Accelerated Service Release Valve
7.7.32 Install a NEW accelerated release check valve (30)
into the service portion filling piece (31).
7.7.33 Install the check valve spring (29) into the filling piece
(31) so that it seats on the check valve (30), then install the
spring seat (28) to retain the parts in place.
7.7.34 Place a NEW filling piece gasket (32) and the service
portion filling piece (31) in position on the body (49).
7.7.35 Apply a light coating of #2 Silicone Grease, Wabtec
Corporation Specification M-07680-02, to the surfaces of a
NEW 1/4" O.D. o-ring (26). Also lightly lubricate the o-ring
groove on the service accelerated release valve plunger (25)
and the bearing surfaces of the plunger bushing of the filling
piece.
7.7.36 Install the NEW lubricated 1/4" O.D. o-ring (26) into
its groove on the short end of the service accelerated release
valve plunger (25), then install the plunger with o-ring (26,25)
into the filling piece (31), longer end of the plunger first.
7.7.37 Using theAccelerated Release Valve Piston Spanner
Wrench, as shown in Figure 10, to hold the service
accelerated release valve piston (24), install a NEW
diaphragm (23) onto the piston (24) so that the part number
on the diaphragm faces away from the piston toward the
threaded end.
7.7.38 Install the diaphragm follower (22) and lightly coat
the threads of the service accelerated release valve piston