BENDIX MV-2 CONTROL MODULE User manual

1
®
SD-03-3412
FIGURE 3
DESCRIPTION
TheBendix®MV-2™controlmoduleisanintegratedcontrol
assembly designed for control panel mounting in a
truck-tractor. The bodies for the module, as well as “spool”
inserts,aremoldedofanonmetallic,noncorrosivematerial.
The assembly consists of two push-pull valves and a dual
circuit supply valve which triggers at a preset pressure
differential. The valve “spool” inserts, as well as the dual
circuitsupplyvalvespoolandshuttle, mayberemovedfrom
thevalvebodieswithout disconnecting the air lines.
TheMV-2™moduleprovides all the functions of a standard
three valve combination plus supply reservoir source
selection:
1. Tractorprotectioncontrol
2. Trailerservice air supply
3. System park
4. Trailerpark only
5. Trailercharge with tractor spring brakes applied(tractor
parkonly)
6. Supplyreservoir selection
The MV-2™module includes a spring loaded dual circuit
supplyvalve whichselects,asthe airsourceforboth control
valves,the No.1reservoir at alltimesunless thepressurein
theNo. 1 reservoirfallsnotmore than 30 P.S.I.below that of
the No. 2 reservoir, when the dual circuit supply valve will
shuttle and establish the No. 2 reservoir as the supply.An
auxiliaryairdelivery port is also available which receives its
supplyfrom the dual circuit supply valve.Allair connections
areatthebottomofthevalve,asshownonFigure3,including
theauxiliaryairdelivery port.
RESERVOIR#1
RESERVOIR#2
RESERVOIR#2
SUPPLY
RESERVOIR#1
SUPPLY
PORTDESIGNATIONS
MV-2™CONTROL
MODULE
AUXILIARYAIR
DELIVERY
DELIVERY-TRACTOR
SB-3
EXHAUST
DELIVERY-TRAILER
TP-3™
TRACTOR
PROTECTION
VALVE
Bendix®MV-2™Control Module
1
RED
YELLOW
COVER(1)
5
FIGURE 1 FIGURE 2
2
9347
8
6

2
FIGURE 4
FIGURE 5
Thetrailerairsupplyvalve(redbutton)(seeFigure1)delivers
air to the trailer supply line and also will trip (Pop out)
automatically and shut off the trailer supply if pressure
decreases to 40 ±5 P.S.I.
NOTE: ReservoirNo.1 must be the reservoir that supplies
therear tractor axle(s).
ReservoirNo.2 must be the reservoir that supplies
thefront axle.
Theparkingbrakevalve (yellow button) controls the spring
brakesonthetractorand when exhausted, simultaneously
causes the trailer supply valve to trip and exhaust, thus
applyingbothtractorand trailer parking brakes as required
by Federal Regulations. The trailer brakes may be
independentlyreleased bypushingonly thetrailerair supply
valve(red button)in.
OPERATION
Initial Charge
With the system completely discharged, both buttons are
out (Figure 4). When system pressure reaches 65 P.S.I.,
the red button (trailer supply) may be pushed in (Figure 5)
andshould stayin,charging thetrailersystem andreleasing
thetrailerbrakes.Theyellowbuttonmaynowbe pushed in
which will supply air to the tractor spring brakes, releasing
them.
Normal Operating Position (Figure 7)
With both buttons pushed in, air is now being supplied to
the trailer and to the tractor spring brakes; all brakes are
released.
Actuation of Trailer Park or Emergency Brakes
(Figure 6)
To actuate the trailer brakes only, the red button is pulled
out,exhausting the trailer supply line. The trailerbrakesare
now applied either by air emergency or spring brakes,
depending on the type of trailer system. This mode would
be used to uncouple from the trailer and during bobtail
operation.
System Park (Figure 4)
With both buttons in for normal run modes, the parking
brakeson bothtractorandtrailer maybeactuated by pulling
the yellow (parking brake) button out, which exhausts the
airfromthetractorspringbrakes andsimultaneouslycauses
thered(trailersupply)buttontopop out, applying the trailer
brakes. This complies with Federal Regulations that one
control must apply all the parking brakes on the vehicle.
Trailer Charge (Figure 5)
Ifbothvalvesare out,parkingthecombinationvehicle,andit
is desired to recharge the trailer (leaving the tractor spring
brakes applied,) the red button may be pushed in
repressurizingthe trailer supply line. This modemight also
be used to park a combination vehicle with air actuated
emergency brakes on the trailer to provide demonstrated
parking capability with tractor spring brakes only.
Automatic Application
With both buttons in, in the normal run configuration, if the
supply pressure to the push-pull valves is reduced to
40 ±5 P.S.I., the red button (trailer supply valve) must pop
out,applying theemergencyor parkingbrakesonthe trailer.
If the red button is held in manually and the pressure
decreases to 30 ±5 P.S.I., a tripper piston within the trailer
controlspoolwillmoveupward,exhaustingthetrailersupply,
effectingtherequirednon-overridefeature.Theyellow(parking
brake) button will pop out at approx. 20-30 P.S.I.
PREVENTIVE MAINTENANCE
Important: Review the Bendix Warranty Policy before
performinganyintrusivemaintenanceprocedures.Awarranty
maybe voided if intrusive maintenance is performedduring
thewarranty period.
No two vehicles operate under identical conditions, as a
result, maintenance intervals may vary. Experience is a
valuableguide indeterminingthebest maintenance interval
for air brake system components.At a minimum, the MV-2™
module should be inspected every 6 months or 1500
operatinghours,whichevercomesfirst,forproperoperation.
Should the MV-2™module not meet the elements of the
operationaltestsnotedinthisdocument,furtherinvestigation
andservice of the valve mayberequired.
SERVICE
RESERVOIR#1
SERVICE
RESERVOIR#2
SYSTEMPARK
TRACTORSPRINGBRAKECONTROL
SUPPLYTOTRAILER
MV-2™
CONTROL
MODULE
EXHAUST
QRV
SB-3
TP-3™
TRACTOR
PROTECTION
VALVE
SERVICE
RESERVOIR#1
SERVICE
RESERVOIR#2
CHARGETRAILERWITH
TRACTOR PARKED
TRACTORSPRINGBRAKECONTROL
SUPPLYTOTRAILER
MV-2™
CONTROL
MODULE
QRV
SB-3
TP-3™
TRACTOR
PROTECTION
VALVE
EXHAUST

3
FIGURE 6
FIGURE 7
OPERATING & LEAKAGE TEST
1. Charge the air brake system to 65 P.S.I. and check for
leakage between body seals, body and cover plates.
Noleakagepermitted.
2. Withsupplypressure stillat65P.S.I.,pushtheredbutton
in. The button must stay in. Leakage at the exhaust
port must not exceed a 1" bubble in 5 seconds.
3. Developaleakinthelinedeliveringairtothetrailersupply
circuit. The red button must pop at 40 ± 5 P.S.I. and
maintain the supply pressure. Leakage at the exhaust
port must not exceed a 1" bubble in 5 seconds.
4. Hold the red button in and again develop a leak in the
supplycircuit.Airmust start to escape from the exhaust
port when the trailer supply line pressure reaches
30 ±5 P.S.I.
5. Releasetheredbuttonand rebuild the supply pressure
toatleast40 P.S.I. Push in the yellow button; the yellow
buttonmustremainin.Leakageattheexhaustportshould
not exceed a 1" bubble in 5 seconds.
6. Developaleakinthe tractorspringbrake deliverycircuit.
Theyellow button must pop at 25±5P.S.I.and maintain
supply pressure. Leakage at the exhaust port should
not exceed a 1" bubble in 5 seconds.
7. Charge the system to 120 P.S.I. and push both buttons
in.Pulltheredbuttonout.Theyellow buttonmustremain
in.
8. Push the red button in and pull the yellow button out.
Theredbuttonmustpopoutalmost instantaneously.
9. Install a gauge to monitor tractor spring brake delivery
pressure. Apply 120 P.S.I. to both reservoirs (No. 1 &
No. 2). Push in the yellow button. Delivery pressure
should equal the pressure in reservoir No. 1. Reduce
the pressure in No. 1 reservoir. Delivery pressure and
No. 1 reservoir pressure should descend together to
105-90P.S.I.at which point the dual circuit supply valve
shuttle should switch to No. 2 reservoir and delivery
pressure should increase to No. 2 reservoir pressure.
After the No. 1 reservoir pressure is reduced to zero,
thereshouldnot beaudibleleakageattheNo.1reservoir
opening. Close the leak which had been created in the
No. 1 reservoir.
10.Leavingtheyellowbuttonin,rechargetheNo.2reservoir
to 120 P.S.I. The delivery pressure should also read
120 P.S.I. Recharge the No. 1 reservoir to 100 P.S.I.
Slowly vent the No. 2 reservoir. As the No. 2 reservoir
pressure and the delivery line pressure descend,
pressure should stabilize at approx. 100 P.S.I.
11. Close all vents or leakage points and charge both
reservoirs to 120 P.S.I. Position the red button out and
the yellow button in. Develop a leak in the spring brake
deliverylineandholdtheyellowbuttonin.No.1 reservoir
pressure must reduce to zero and No. 2 reservoir
pressure to 20 - 30 P.S.I. The dual circuit supply valve
shuttleshouldcycleseveraltimesduring this leakdown
period.
REMOVINGAND REPLACING SPOOLASSEMBLIES
Blockthewheelsorotherwisesecure the vehicle and drain
allreservoirs.ItshouldbeunnecessarytoremovetheMV-2™
modulefromthevehicle.Removeanypanel,plateorwhatever
is necessary to expose the valve cover plates. It is
recommended that the valve be serviced by replacing the
complete spool assemblies. The dual circuit supply valve
feature may be serviced by replacing four (4) o-rings and
one(1)spring, available in a maintenance kit.
DISASSEMBLY- Spools (Figure 2)
1. Remove the cover plate screws. (Four in each cover)
andcover(1).
2. Carefullypullthespoolassembliesoutoftheirrespective
body bores by pulling on the buttons.
3. Removetherollpins(2)which retain the buttons on the
spoolstemsandremove buttons and cover plates.
SERVICE
RESERVOIR#1
SERVICE
RESERVOIR#2
PARKTRAILERWITH
TRACTOR RELEASED
OR BOBTAIL TRACTOR
TRACTORSPRINGBRAKECONTROL
SUPPLYTOTRAILER
MV-2™
CONTROL
MODULE
EXHAUST
QRV
SB-3
TP-3™
TRACTOR
PROTECTION
VALVE
SERVICE
RESERVOIR#1
SERVICE
RESERVOIR#2
NORMAL OPERATING
POSITION
TRACTORSPRINGBRAKECONTROL
SUPPLYTOTRAILER
MV-2™
CONTROL
MODULE
QRV
SB-3
TP-3™
TRACTOR
PROTECTION
VALVE
EXHAUST

4
BW1584 © 2004 Bendix Commercial Vehicle Systems LLC. All rights reserved. 3/2004 Printed in U.S.A.
DISASSEMBLY - Dual Circuit Supply Valve
1. The dual circuit supply valve is located in the tractor
control body. (The one from which the spool with the
yellowbuttonhasbeenremoved.)Graspthewebinthe
top of the valve spool (3) (Figure 2) with narrow nose
pliers,twistandpullvalvespoolout.Theshuttle(4)should
alsocome out with the spool.Removetheshuttlereturn
spring(5)ando-rings (6), (7), (8) and (9).
CLEANING & INSPECTION
The non metallic components which comprise most of the
parts of the MV-2™module should not be immersed in
any solvent type cleaner. Old lubricant should be wiped
off parts to be reused and the bores of the body wiped out
with a clean dry cloth.
ASSEMBLY - Dual Circuit Supply Valve (Figure 2)
Lubricate o-rings, bore and sliding surfaces with silicone
lubricantBendix291126BW-650-MDow Corning 55-M.
1. Place the shuttle return spring (5) in the dual circuit
supplyvalveboreinthebody.
2. Installo-rings(6) & (7) on the shuttle (4) and(8)&(9)on
thevalve spool (3).
3. Insertthesmall end of the shuttle in the spoolandinsert
theassemblyintothevalvebore, flush with top of body.
Thedualcircuitsupplyvalvespool isretainedinthebody
by the same cover plate which also retains the tractor
control(yellowbutton)spool.
ASSEMBLY- SPOOLS
If old spools are being used, the o-rings and all sliding
surfacesshouldbelubricatedwithBendixBW-650-MSilicone
Lubricant (291126). If new service replacement spools are
beinginstalled,they will be pre-lubricated.
1. Place cover plates over each plunger stem. The cover
plates are identical and are installed convex side up.
2. Place the red button on the longer spool (for trailer air
supply),matchingthegrooveinthebuttonwiththetongue
in the cover plate (where applicable), and secure the
button with the button roll pin. Place the yellow button
on the shorter spool (for tractor air supply), matching
button and cover (where applicable) and securing with
buttonroll pin as before. If new servicespoolsareused,
a new roll pin will be found in each spool package.
3. Inserttheshorterspool assembly (yellow button) in the
tractorsupply bore (housing withthedualsupplyvalve).
Ifthe entire valve assemblyhasbeenremoved, position
theassemblysothatthetractorcontrolbodyhousing is
at 3 o’clock. With the open bore (trailer supply) at 9
o’clock, rotate the button until wording on top-center is
horizontallyreadable.Thesteppedsideofthecoverplate
should be covering the dual supply valve. Secure the
platewith the four flat head Phillips screws;torqueto25
inch pounds. Insert the longer spool assembly (red
button)inthe remaining bore. The stepped sidesof the
cover plates should key with each other when the
remaining four flat head screws are torqued to 25 inch
pounds.
SERVICE TEST
Repeatthe“Operating and LeakageTest”.
WARNING! PLEASE READ AND FOLLOW
THESE INSTRUCTIONS TO AVOID
PERSONAL INJURYOR DEATH:
When working on or around a vehicle, the following
general precautions should be observed at all times.
1. Park the vehicle on a level surface, apply the
parking brakes, and always block the wheels.
Always wear safety glasses.
2. Stop the engine and remove ignition key when
working under or around the vehicle. When
working in the engine compartment, the engine
should be shut off and the ignition key should be
removed. Where circumstances require that the
enginebe in operation,EXTREME CAUTION should
be used to prevent personal injury resulting from
contact with moving, rotating, leaking, heated or
electrically charged components.
3. Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Useonly the proper tools and observe
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems,make certainto drainthe airpressure from
all reservoirs before beginning ANY work on the
vehicle. If the vehicle is equipped with an AD-IS™
air dryer system or a dryer reservoir module, be
sure to drain the purge reservoir.
5. Following the vehicle manufacturer’s
recommendedprocedures, deactivate the electrical
system in a manner that safely removes all
electrical power from the vehicle.
6. Never exceed manufacturer’s recommended
pressures.
7. Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove a
component or plug unless you are certain all
system pressure has been depleted.
8. Use only genuine Bendix®replacement parts,
components and kits. Replacement hardware,
tubing, hose, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically for such applications and
systems.
9. Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifically stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certainallcomponentsandsystemsarerestoredto
their proper operating condition.