BENDIX BA-921 COMPRESSOR-STD-CLOSED ROOM User manual

1
GENERAL
For genuine Bendix remanufactured compressors not
equipped with a drive gear, it is necessary to remove the
existing gear from the old compressor and reinstall it on the
new remanufactured compressor.
NOTE: It may be necessary to remove the ttings from the
cylinder head prior to removing the gear to prevent damage.
IMPORTANT
The Bendix remanufactured compressor is equipped with
a new safety valve. Do not reuse the old safety valve.
KIT COMPONENTS
• Genuine Bendix remanufactured BA-921 Compressor
(including safety valve)
GEAR REPLACEMENT PROCEDURE
1. After removing the old compressor from the engine,
place the compressor with drive gear facing upward so
it can be removed safely. NOTE: It may be helpful to
secure the compressor and gear so that the gear does
not rotate and the lock nut can be removed more easily.
See Figure 1.
Figure 1 – Remove the Bendix®BA-921®Compressor
Bendix®BA-921®Compressor Gear Replacement for Detroit®Diesel Corporation (DDC)
Engines DD13®and DD15®
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
compar tment, 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,
fi ttings, wiring, etc. must be of equivalent size, type, and
strength as original equipment and be designed specifi cally
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 specifi cally 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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Secure the compressor in a vise to help mitigate risk of
personal injury.
2. Using a pneumatic or electric torque gun with a 27-mm
socket, loosen the lock nut by turning it clockwise (this
is a left-hand threaded lock nut). Leave the lock nut
partially threaded on the crankshaft to prevent the gear
from fully dislodging. See Figure 2.
Figure 2 – Loosen the Lock Nut
3. Position a gear puller on the drive gear and hand snug
the puller screw against the crankshaft. Bendix suggests
a gear puller like the one shown in Figure 3 that uses
a retaining cage to help position and secure the puller
arms. See Figure 3.
Figure 3 – Gear Puller
4. Again, using a pneumatic or electric torque gun with a
27-mm socket, tighten the gear puller screw until the
compressor drive gear comes loose from the crankshaft.
The lock nut should capture the gear and prevent it from
coming completely o󰀨. See Figure 4.
The drive gear may quickly "pop" free during this step.
Extra caution is necessary to prevent personal injury.
Figure 4 – Loosen the Compressor Drive Gear
5. It is now safe to remove the gear puller and lock nut from
the crankshaft. Once the lock nut is removed, the gear
can slide o󰀨. See Figure 5.
Figure 5 – Slide Off the Gear

3
6. Once the gear is removed, thoroughly clean the gear
and inspect it for any physical damage. See Figure 6.
Figure 6 – Clean and Inspect the Gear
7. Secure the remanufactured compressor with the
crankshaft oriented upward, and carefully place the
salvaged drive gear on the crankshaft ensuring it is
square. See Figure 7.
Figure 7 – Place the Drive Gear on the Crankshaft
8. Replace the lock nut and hand tighten counter-clockwise
(this is a left-hand threaded lock nut). See Figure 8.
Figure 8 – Replace the Lock Nut
9. Once the lock nut is snug, use a torque
wrench to secure the lock nut to 165-200 ft-lbs
(220-280 N•m). Ensure the crankshaft is secure while
torquing the lock nut. See Figure 9.
Figure 9 – Secure the Lock Nut
10. Reinstall the compressor – and any ttings that were
removed – per the engine manufacturer's specications.

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ADDITIONAL INFORMATION
Visit b2bendix.com for all related spare parts and service kits.
NOTE: Bendix recommends replacing the power steering
pump mounting gasket, o-ring, and oil seal with genuine
OE parts.
The following torque specications are for reference only.
Refer to the engine manufacturer's specications.
Fitting Torque
Coolant Fitting
M18 x 1.5-6H
40-45 N•m
354-398 in.-lbs
Air Discharge Port Fitting
M26 x 1.5-6H
80 +/- 12 N•m
708 +/- 106 in.-lbs
Unloader (Governor) Port Fitting
ISO 6149-1, M10 x 1-6H
15 +/- 2.2 N•m
133 +/- 19 in.-lbs
Power Steering Pump Screw
M8 x 1.25-6H
50 + 8 N•m
443 + 71 in.-lbs