BENDIX BW2763 Dépliant

1. Chock the vehicle wheels. Start the engine and charge the air brake system to

governor cut-out, around 130 psi.

2. The primary and secondary air gauges will start to rise. As the system pressure

reaches the cut-out pressure, the gauges will stop moving and the air dryer will
purge. When the air dryer purges, the secondary gauge will drop 8 to 14 psi.

3. Shut off the engine and push in the yellow button to release the parking brakes.

Note that the gauges will drop a small amount. Check the air gauges and
if either gauge indicates a continued loss of pressure, check the system for
leaks.

4. Apply and hold the service brakes by fully depressing the brake pedal. The

gauges will drop a small amount. Again, check for a loss of pressure by watching
both gauges. If either gauge indicates a continued loss of air pressure, check
the system for leaks.

5. Release the service brakes. Continue to apply and release the service brakes

until the pressure drops below governor cut-in (approximately 100 psi). Both
gauges will show a drop in pressure with each brake application. If the system
air pressure goes below 60 psi, the low pressure indicators will activate.

F i e l d I n s p e c t i o n

6. Start the engine and charge the air brake system again. Turn the engine off.
7. Locate and drain the primary reservoir. Both dash air gauges will indicate

a pressure drop. The secondary reservoir, which is not being drained, will
stop showing a drop in pressure above 90 psi. If both continue to drain, this
indicates that the secondary reservoir has a defective, or missing, pressure
protection valve such as the SC-PR

™

single check protection valve.

8. Install or service the SC-PR

™

single check protection valve in the air brake

system as shown in the schematic below.

9. Start the engine and charge the air brake system again. Turn the engine off.
10. Locate and drain the secondary reservoir. As this reservoir is drained, only the

secondary gauge should indicate a pressure drop. If both continue to drain, this
indicates that the primary reservoir has a defective, or missing, single or one
way check valve.

11. Replace the existing, or install a new, single check valve in the primary reservoir

supply port.

Delivery

Port

Control Port

Compressor

Secondary

Reservoir

SC-PR

™

Single Check Protection Valve

Primary

Reservoir

Engine Turbo

Exhaust

Port

Turbo Cutoff

Governor

Supply

Reservoir

WARNING: Be sure to follow all the General Safety

Guidelines outlined in the AD-SP

Service Data Sheet,

SD-08-2415, before performing any service on the air

brake system.

Bendix

AD-SP

Air Dryer System

AD-SP

Air Dryer

Purge Cycle