7
ASSEMBLY
Prior to reassembling the SR-4
™
valve, lubricate all o-rings,
o-ring grooves, piston bores, and metal to metal moving
surfaces with Bendix silicone lubricant BW-650-M piece
number 291126.
IMPORTANT NOTE: When pipe thread sealant is used
during assembly and reinstallation, particular care
should be taken to assure that this material does
not get into the valve itself. Pipe sealant should be
applied beginning with the second thread back from
the end.
ASSEMBLY
TYPE 1 SR-4
™
VALVE (REFER TO FIG. 4)
RESERVOIR FITTING (CHECK VALVE “C”) AND
INLET EXHAUST VALVE
1. Place reservoir fitting (13) in a vise, pipe threads
down.
2. Insert the check valve (26), check valve spring (25),
valve retainers (24), and retaining ring (23).
3. Install the fl at inlet exhaust valve into the valve body.
NOTE:
The fl at side of the valve with the four ears protruding
rests against the inlet and exhaust seat.
4. Place the inlet exhaust valve spring (15) in positions
on the inlet exhaust valve.
5. Properly align the reservoir fi tting assembly (13) and
install in body. Torque to 200 to 300 inch pounds.
ASSEMBLY - CONTROL PISTON AND COVER
6. Install the three o-rings (10, 11 & 12) on the control
piston (9).
7. Position the control piston return spring (8) in the body
and install the control piston.
8. Install the seal ring (7) in the groove on the control
piston cover and assemble the cover to the body.
Tighten the cap screw to 40-60 inch pounds.
ASSEMBLY - PRESSURE PROTECTION VALVE
9. Install the o-ring (5) on the pressure protection piston
(3) and the rubber inlet exhaust valve over the stem.
NOTE: Light lubrication of the piston stem will facilitate
the rubber valve installation.
10. Install the pressure protection piston assembly in the
valve body and position the pressure protection spring
on the piston.
11. Position the spring retainer on top of the pressure
protection piston assembly and secure with the four
round head machine screws. Torque to 20-30 inch
pounds.
ASSEMBLY - CHECK VALVES “A” AND “B”
1. Twist the check valves (21) into the springs (20) and
place in their respective bores, and install the socket
head pipe plugs. Torque to 140-170 inch pounds.
ASSEMBLY - EXHAUST CHECK VALVE
1. If so equipped, position the diaphragm (19), washer
(18) and screw (17) in the control piston exhaust port.
Torque the screw from 15 to 25 inch pounds.
ASSEMBLY TYPE 2 SR-4
™
VALVE (REFER TO
FIG. 5)
1. Install diaphragm (14) into the exhaust port of the SR-4
™
valve. Retain with the diaphragm washer and Phillips
head screw. Tighten securely.
2. Twist the conical spring (12) onto the spring seat and
the opposite end onto the check valve (13), install this
subassembly into the check valve housing, depress
the spring seat and install the snap ring making sure it
is fully seated in its groove.
3. Install the inlet/exhaust valve (10) into the RES-1 port
making sure the fl at side of the valve is against the inlet
seat. Install spring (9) into the valve making sure it is
installed over the rubber protrusion of the valve (10).
4. Install the o-ring (11) into the groove on the check valve
assembly. Thread the check valve assembly into the
RES-1 port. Lightly clamp the SR-4
™
valve body in
a vise and using a 1-1/4 inch end wrench torque to
150-400 inch pounds.
5. Place the spring (6) into the large bore of the SR-4
™
valve body making sure it is seated in the base of the
bore. Install the o-ring (7 & 8) onto the piston. Place
the piston into the housing with the small end inside of
the spring (6).
6. Install the sealing ring (5) into its groove on the end
cover. Install the end cover over the piston, installed in
Step 5, with the trailer supply port oriented towards the
exhaust port. Retain with the four 1/4 inch cap screws,
torque to 30-60 inch pounds.
7. Refer to Fig. 2. Install the four check valve assemblies
(4) into the cavities of the SR-4
™
valve and retain
with the 3/8 inch pipe plugs. Removed in Step 3 of
“Disassembly”. Apply a thread sealant or Tefl on tape
to the threads of the pipe plugs and torque to 130-170
inch pounds.
8. Install the two piston assemblies (3) into their cavities,
place the spring (1 & 2) over the bosses of the piston
assemblies.
CAUTION:
THE SPRING COLOR CODED
WHITE MUST BE INSTALLED ON THE PISTON
CLOSEST TO THE END COVER AND THE GREEN
COLOR CODED SPRING ON THE PISTON AWAY
FROM THE END COVER. Place the spring retainers
over the springs and retain with the eight #10 cap
screws. Torque to 20-30 inch pounds.
