BENDIX BW2369 Data Sheet

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The compressor's discharge valves are part of the valve 
plate assembly.  The inlet reed valve/gasket is installed 
between the valve plate assembly and the top of the 
crankcase.
The cast iron crankcase houses the piston assembly, 
connecting rod, crankshaft and related bearings.
All Bendix
®
 BA-921
®
 compressors are equipped with a 
safety valve to protect the compressor head in the event 
of, for example, a discharge line blockage downstream 
of the compressor.  Excessive air pressure will cause the 
safety valve to unseat, release air pressure and give an 
audible alert to the operator.  The safety valve is installed 
in the cylinder head safety valve port, directly connected 
to the cylinder head discharge port.
The crankcase cover located at the bottom of the crankcase 
is stamped with information identifying the compressor 
model, customer piece number, Bendix piece number and 
serial number.  See Figures 1 and 4.
OPERATION
The compressor is driven by the vehicle's engine and 
functions continuously while the engine is in operation.  
Actual compression of air is controlled by the compressor 
unloading mechanism operating in conjunction with a 
governor.
Compressor Model, 
Customer Piece Number, 
Bendix Piece Number and 
Serial Number shown here
FIGURE 4 - CRANKCASE BASE COVER 
FIGURE 3 - BENDIX
®
 BA-921
®
 COMPRESSOR (CUT-AWAY) (STANDARD AND CLOSED ROOM)
Unloader
Piston
Piston 
Rod
Coolant Ports 
(3 total)
Piston
Air 
Intake
Unloader 
Cover
Discharge
Reed  
Valves (2)
Crankshaft
Cooling 
Plate
Crankcase 
Cover
Splash
Shield
Unloader
Piston
Piston 
Rod
Coolant Ports 
(3 total)
Piston
Unloader 
Cover
Discharge
Reed  
Valves (2)
Crankshaft
Cooling 
Plate
Crankcase 
Cover
Closed Room
Standard
FIGURE 5 - TYPICAL COMPRESSOR DRIVE FLANGES
Detroit 
Diesel S60
Caterpillar
HD Acert 
Engines
Caterpillar
C7, C9 
Engines