Bendix Commercial Vehicle Systems SR-5 TRAILER SPRING BRK VALVE 4/11 - Manual (Page 9)

9
DISASSEMBLY
The following procedure is for reference only. Always have
the appropriate maintenance kit on hand, and use its
instructions in lieu of those presented here. Refer to Figure
9 throughout the procedure.
1. Remove the four screws(1) that secure spring retainer(2)
to the valve body. Note that the retainer is spring-loaded.
Remove the screws while holding the retainer against
its spring load. Then slowly remove the retainer.
2. Remove spring(3) and piston assembly(4).
3. Remove piston o-ring(5). Do not remove the retaining
ring and stem from the piston. The piston is serviced as
an assembly.
4. Note and mark the position of control piston cover(7).
Then remove the four screws(6) that secure the cover
to the body.
5. Remove cover(7) and sealing ring(8), control piston(9),
and spring(10).
6. Remove o-rings(11 & 12) from piston assembly.
7. Remove reservoir fitting(13) and o-ring(14).
8. Remove spring(15) and inlet/exhaust valve(16).
9. Remove the pipe plugs that retain the three single check
valves. Two check valves are in the body, and one is in
the cover(7).
10. Remove check valve springs(17) and rubber check
valves(18).
11. With a pair of I.D. snap ring pliers, remove the snap
ring(19) in the end of the reservoir fitting check valve
assembly. Remove spring seat(20), spring(21), and
check valve(22).
12. Remove screw(23), washer(24), and diaphragm (25)
from the exhaust port.
CLEANING AND INSPECTION
1. Inspect all parts for excessive wear or deterioration.
Inspect valve seats for nicks or burrs. Check the springs
for cracks or corrosion.
2. Inspect the bores of the valve housing for deep scuffing
or gouges.
Replace all non-metallic parts and any part not found to be
serviceable during inspection, using only genuine Bendix
replacement parts.
ASSEMBLY
Before assembling the SR-5 ™ 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.
NOTE: When using pipe thread sealant during assembly
and installation, take particular care to not allow
the sealant into the valve itself. Apply the sealant
beginning with the second thread back from the end.
1. Twist the springs(17) on each of the check valves(18).
Drop the assemblies into their respective bores in the
valve body and install the pipe plugs. Torque the plugs
to 140-170 inch pounds.
2. Place reservoir fitting(13) upright, pipe threads down.
Drop check valve(22) into place. Install check valve
spring(21), spring seat(20), and snap ring(19). Install
o-ring(14) into fitting.
3. Install inlet/exhaust valve(16) into valve body. NOTE: The
side with four protruding ears rests against the seat in
the body.
4. Place spring (15) in position on the inlet/exhaust valve.
Make sure the spring rests evenly on the four ears of
the inlet/exhaust valve and the rubber protrusion on the
valve fits into the spring’s inner diameter.
5. Properly align the inlet/exhaust valve springboard in the
recess at the end of the reservoir port fitting(13). Install
the fitting into the valve body. Torque to 200-300 inch
pounds.
6. Install o-rings(11 & 12) into their respective grooves in
control piston(9).
7. Drop and position spring(10) into the valve body.
8. Make sure all parts are properly aligned, and install the
control piston(9) into the valve body.
9. Install sealing ring(8) in cover(7), and install cover onto
valve body, using the identification made in
DISASSEMBLY step 4. Torque screws(6) to 40-60 inch
pounds.
10. Install o-ring(5) in its groove in the pressure protection
piston(4). Install the piston assembly into the valve body.
11. Position the spring(3) and spring retainer(2) on top of
the pressure protection piston assembly, and secure
with the four screws(1). Torque to 20-30 inch pounds.
12. Install diaphragm(25), washer(24) and screw(23) into the
exhaust port. Torque screw to 15-25 inch pounds.
NOTE: BEFORE PLACING THE VEHICLE BACK INTO
SERVICE, PERFORM “OPERATIONAL AND
LEAKAGE TESTS,” LISTED IN THIS MANUAL.
BW1680 © 2007 Bendix Commercial Vehicle Systems LLC. All rights reserved. 3/2007 Printed in U.S.A.