BENDIX® PP-1® & RD-3™ CONTROL VALVES MAINTENANCE KIT

Bendix® RD-3™
Push Type Control
Valve

Panel
Mounting
Nut
4

Bendix® PP-1®
Control Valve

Roll-Pin

Plunger

Spring

Spring

1

Panel
Mounting
Nut
4

Roll-Pin
Plunger

3

3

1

2

5
Cap Screws (x2)

2

5
Cap Screws (x2)
Figure 2

Figure 1

2
1

5
4

3

Kit Contents
Item No.

Description

Qty.

1

Sealing Ring

1

2

Locknut

1

3

Inlet and Exhaust Valve

1

4

Plunger O-Ring

1

5

Washer

1

6

Tube of Lubricant

1

6
Figure 1 – Bendix® PP-1® & RD-3™ Control Valves Maintenance Kit Contents
1

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, a Bendix ® AD-9si ®, AD-HF®,
or AD-HFi ® 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.

2

REMOVAL

Block and/or hold the vehicle by a means other than the
air brakes and drain all reservoirs.
1. Drive the button roll-pin out with a punch and remove
the button.
2. Disconnect the air fittings, identify supply and delivery
lines, remove the panel mounting nut, and remove the
valve.

DISASSEMBLY

1. Remove the two cap screws which retain the lower
cover and remove the cover. Remove the sealing
ring (1) and discard.
2. Insert a small punch through the roll pin hole in the
stem and remove the locknut (2) with a 7/16" wrench.
Discard the locknut (2).
3. Remove the inlet/exhaust valve (3), plunger, spring,
and washer (5) and discard items 3 and 5.
4. Remove the plunger o-ring (4) from the plunger and
discard.

REASSEMBLY

1. Before reassembly, clean all parts and coat the plunger
bore and o-ring grooves with the lubricant (6) provided.
2. Install the plunger o-ring (4) on the plunger.
3. Install the plunger spring on the plunger and insert and
hold it in the valve body.
4. Install the inlet/exhaust valve (3) and washer (5) on
plunger and tighten the locknut (2) to 20-25 in-lbs torque.
5. Install the sealing ring (1) on the cover and install the
cover on the body. Tighten the cap screws to 30-60 in-lbs
torque.

OPERATING AND LEAKAGE TESTS

Do not install fittings or tubing into the exhaust port
if used for parking brake control. If a worn PP-1 or
PP-8 valve is used for parking brake control and
the exhaust plumbing is kinked, bent, or restricted,
the vehicle might not park, and a roll away may
result, potentially resulting in injury or death.

INSTALLING

1. Install the valve in the panel, securing with the panel
mounting nut.
2. Reconnect the air lines and check for proper piping of
the supply and delivery lines.
3. Install the operating button. Secure the operating button
by installing the roll pin.
For additional information on the PP-1 or RD-3 valves,
reference the Service Data sheet SD-03-3611 on
B2Bendix.com.

1. Run the vehicle until the air system reaches full
reservoir pressure (120-135 psi). Turn off the vehicle.
2. Move the control valve button & plunger from side to
side and up and down. Do not push the button in. If
there is any play, or if audible leakage is detected, the
valve must be replaced.
3. Identify the dash valve exhaust hose location – if there
is a hose still connected to the Park Control Valve
Exhaust Port, it is advised to disconnect it and remove
any fitting.
4. With the button pulled out (exhaust position), rotate the
button and plunger in a clockwise direction – stopping
every 90º to check for leakage.
5. Using a soap solution, check for leaks. The allowable
leakage should not exceed a 1” bubble in 5 seconds
at any location on the valve.
6. Push the button in (applied position) and check for
leaks. (The Bendix® RD-3™ valve will have to be
manually held in this position.) The leakage should
not exceed a 1” bubble in 3 seconds at any location
on the valve.
7. Reduce the supply pressure. At a pressure from 60
to 20 psi, depending on the part number specific
automatic release pressure, the button should pop
out automatically, exhausting the delivery volume.
(This does not apply to the RD-3, PP-8 or some
PP-1 valves without an automatic release pressure).

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S-0266 Rev. 003 © 2024 Bendix Commercial Vehicle Systems LLC, a member of Knorr-Bremse • 3/24 • All Rights Reserved