BENDIX DV-2 Mounting instructions

1
®
DESCRIPTION
The Bendix®DV‑2™automatic reservoir drain valve ejects
moisture and contaminants from the reservoir in which it
is connected. It operates automatically and requires no
manual assistance or control lines from other sources.
The automatic reservoir drain valve has a die cast
aluminum body and cover, and is normally mounted either
in the bottom of the reservoir – using the top port of the
drain valve, or in the end of an end drain reservoir – using
the side port of the valve.
The DV‑2 drain valve is also available with a heater and
thermostat cast into the cover for vehicles operated in
subfreezing temperatures. The heated DV‑2 valve is
supplied in either a 12 or 24 volt model and in a bottom
or end drain conguration. A 1/4” male pipe adapter is
supplied with all DV‑2 drain valves, end drain and bottom
drain, both standard and heated. This adapter should be
installed directly into the reservoir. Early versions included
a lter screen in the adapter. The lter should be discarded.
Later versions may have a standard pipe nipple instead
of the adapter.
SD-03-2501
Bendix®DV-2™Automatic Reservoir Drain Valve
Standard Bendix® DV-2™
Drain Valve
DV-2 Drain Valve with Heater and Thermostat
Adapter
Body
Top Reservoir
Port
Side
Reservoir
Port
Inlet &
Exhaust
Valve
Thermostat
Housing
Heater Element
Cover
Exhaust PortWire Stem
Electrical Lead
Wire
Valve
Guide
Sealing
Ring
DV-2 Drain Valve
with Heater
Figure 1 – Bendix®DV-2™Drain Valves

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NOTE: If a vehicle equipped with a Bendix®DV‑2™
automatic drain valve(s) is operated in subfreezing
temperatures, it is recommended that a heated reservoir
drain valve be installed.
OPERATION
Referring to Figure 2, with no air pressure in the system,
the inlet and exhaust valves are closed. Upon charging
the system, a slight pressure opens the inlet valve (see
Figure 3) which permits air and contaminants to collect in
the sump. The inlet valve remains open when pressure is
ascending in the system until maximum (governor cut‑out)
pressure is reached. The spring action of the valve guide in
the sump cavity closes the inlet valve. The inlet valve and
the exhaust valve are now closed (as shown in Figure 4).
When reservoir pressure drops slightly (approximately 2
psi), air pressure in the sump cavity opens the exhaust
valve (see Figure 5) and allows moisture and contaminants
to be ejected from the sump cavity until pressure in the
sump cavity drops sufciently to close the exhaust valve.
The length of time the exhaust valve remains open and the
amount of moisture and contaminants ejected depends
upon the sump pressure and the reservoir pressure drop
that occurs each time air is used from the system.
Manual draining can be accomplished as follows:
• Using a tool, move the wire in the exhaust port upward,
holding it in until draining is completed.
• The thermostat on the heated model DV‑2 automatic
drain valve will activate the heating element when the
valve body reaches a temperature of approximately
45°F and will deactivate the heating element when the
valve body is warmed to approximately 85°F.
PREVENTIVE MAINTENANCE
Important: Review the Bendix Warranty Policy before
performing any intrusive maintenance procedures. A
warranty may be voided if intrusive maintenance is
performed during the warranty period.
No two vehicles operate under identical conditions, as
a result, maintenance intervals may vary. Experience is
a valuable guide in determining the best maintenance
interval for air brake system components. At a minimum,
the automatic reservoir drain valve should be inspected
every 6 months or 1500 operating hours, whichever comes
rst, for proper operation. Should the automatic reservoir
drain valve not meet the elements of the operational tests
noted in this document, further investigation and service
of the valve may be required.
GENERAL SAFETY GUIDELINES
WARNING! PLEASE READ AND
FOLLOW THESE INSTRUCTIONS
TO AVOID PERSONAL INJURY OR DEATH:
When working on or around a vehicle, the following
guidelines should be observed AT ALL TIMES:
▲Park the vehicle on a level surface, apply the parking
brakes and always block the wheels. Always wear personal
protection equipment.
▲Stop the engine and remove the 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 engine be in operation, EXTREME CAUTION should be
used to prevent personal injury resulting from contact with
moving, rotating, leaking, heated or electrically-charged
components.
▲Do not attempt to install, remove, disassemble or
assemble a component until you have read, and thoroughly
understand, the recommended procedures. Use only the
proper tools and observe all precautions pertaining to use
of those tools.
▲If the work is being performed on the vehicle’s air brake
system, or any auxiliary pressurized air systems, make
certain to drain the air pressure from all reservoirs before
beginning ANY work on the vehicle. If the vehicle is
equipped with a Bendix®AD-IS®air dryer system, a Bendix®
DRM™dryer reservoir module, or a Bendix® AD-9si®air
dryer, be sure to drain the purge reservoir.
▲
Following the vehicle manufacturer’s recommended
procedures, deactivate the electrical system in a manner
that safely removes all electrical power from the vehicle
.
▲Never exceed manufacturer’s recommended pressures.
▲Never connect or disconnect a hose or line containing
pressure; it may whip and/or cause hazardous airborne
dust and dirt particles. Wear eye protection. Slowly open
connections with care, and verify that no pressure is
present. Never remove a component or plug unless you are
certain all system pressure has been depleted.
▲Use only genuine Bendix®brand replacement parts,
components and kits. Replacement hardware, tubing, hose,
fittings, wiring, etc. must be of equivalent size, type and
strength as original equipment and be designed specifically
for such applications and systems.
▲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.
▲Prior to returning the vehicle to service, make certain all
components and systems are restored to their proper
operating condition.
▲For vehicles with Automatic Traction Control (ATC), the ATC
function must be disabled (ATC indicator lamp should be
ON) prior to performing any vehicle maintenance where
one or more wheels on a drive axle are lifted off the ground
and moving.
▲The power MUST be temporarily disconnected from the
radar sensor whenever any tests USING A DYNAMOMETER
are conducted on a vehicle equipped with a Bendix®
Wingman®system.
▲You should consult the vehicle manufacturer's operating
and service manuals, and any related literature, in
conjunction with the Guidelines above.

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Figure 4 – Inlet and Exhaust Valve Closed Figure 5 – Exhaust Valve Opens
Figure 2 – No Air Pressure Applied Figure 3 – System Charged - Inlet Valve Opens
Upon investigation, parts showing signs of wear or
deterioration should be replaced.
Also, if there is a lter screen in the adapter tting it should
be removed and discarded.
SERVICE CHECKS
OPERATING TEST
With the system charged, make several foot valve
applications while an observer veries that an exhaust
of air occurs from the drain valve during each foot valve
application. If no air comes out, actuate the wire stem. If
air still does not come out, there may be a plugged lter
in the adapter which should be removed and discarded.
LEAKAGE TEST
With system charged and pressure stabilized in system,
there should be no leaks at the drain valve exhaust. A
constant slight exhaust of air at the drain valve exhaust
could be caused by excessive leakage in the air brake
system or contamination.
If the drain valve continues to exhibit leakage at the
exhaust – after inspection and verication of the air brake
system – move the wire stem in the exhaust port upward
to assist with seating the valve in the exhaust port and/or
clearing contamination.
If the Bendix®DV‑2™automatic drain valve does not
function as described, or if leakage is excessive after
repeated attempts to reset the valve, it is recommended
that it be replaced with a new or remanufactured unit or
repaired with genuine Bendix®parts.

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INSTALLING AND REMOVING THE VALVE
REMOVAL
1. Block and hold vehicle by means other than the air
brakes. Drain the air system.
2. Disconnect the heater wire if the valve is so equipped.
Remove the automatic reservoir drain valve.
DISASSEMBLY
1. Remove the four (4) cover cap screws and lock
washers. Remove the cover and sealing ring.
2. NOTE: The heater and thermostat of the Bendix®
DV‑2™drain valve (if equipped) are not serviceable.
If the heater or thermostat has failed, the entire cover
must be replaced. Do not remove the thermostat cover
plate. It is moisture sealed and removal could result in
early thermostat failure.
3. Remove the valve guide.
4. Remove the inlet and exhaust valve.
5. Remove the adapter and lter assembly (if lter is
present).
6. Remove the lter retainer (if any).
7. Remove the lter (if any).
INSTALLATION
1. Block and hold vehicle by means other than the air
brakes. Drain the air system.
2. To avoid early fouling at the DV‑2 valve, thoroughly
nish and clean the reservoir before installing the
drain valve.
3. Aerate any tank thoroughly if any solvents have been
used in the cleaning process.
4.
IMPORTANT When installing a DV‑2 drain
valve equipped with a heater and thermostat, rst
determine if the vehicle electrical system is 12 or 24
volt, and that the heater / thermostat unit is of the same
voltage. The #14 gauge lead wire on the valve should
be connected to the “ON” position of the engine control
or ignition switch. Use an 8 amp fuse for one valve, a
15 amp fuse for two valves, and a 20 amp fuse for three
valves. All electrical connections must be waterproof.
CLEANING AND INSPECTION
1. Cleaning solvent may be used on metal parts. Rubber
parts should be wiped clean.
2. Inspect all parts for wear or deterioration. Discard the
lter screen, if present.
3. Replace all parts not considered serviceable during
these inspections.
4. Bendix maintenance kit part number 282134 contains
all parts necessary for servicing all models of the DV‑2
valve.
ASSEMBLY
1. Before assembling the valve, apply a light lm of grease
on the inlet valve seat.
2. DO NOT APPLY OIL TO THE INLET AND EXHAUST
VALVE.
3. Place the sealing ring in the groove of the cover.
4. Place the valve guide over the inlet and exhaust valve.
5. Place the valve guide and inlet and exhaust assembly
into the cover. Note that the wire will project through
the exhaust port.
6. Place the body on the cover and install the cap screws
and lockwashers.
7. Install the adapter or pipe nipple in the appropriate port.
8. Install the drain valve in the reservoir and reconnect
the heater wire, if the drain valve is so equipped.
9. NOTE: Covers on the standard and heated drain
valves can be interchanged.
TESTING THE REBUILT AUTOMATIC
RESERVOIR DRAIN VALVE
Perform “Operating and Leakage Tests” as outlined in this
document.
SD‑03‑2501 Rev. 008 © 2017 Bendix Commercial Vehicle Systems LLC, a member of the Knorr‑Bremse Group • 10/17• All Rights Reserved
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