 | |
| Illustration 1 | g00529208 |
(1) Air Compressor Governor (2) Air Compressor | |
Air compressor (2) is mounted on the front housing of the engine. The air compressor is driven by an accessory drive gear of the engine.
Clean air enters the air compressor from the intake manifold of the engine. The air compressor is cooled by the engine cooling system and lubricated by the engine lubrication system.
Air compressor governor (1) is fastened to the air compressor. The air compressor governor controls the amount of air pressure in the air system by keeping the air pressure in a limited range. Cut-out pressure for the air compressor governor is approximately 830 ± 35 kPa (120 ± 5 psi). Cut-in pressure for the air compressor governor is approximately 655 kPa (95 psi) .
Air Compressor Governor
 | |
| Illustration 2 | g00435998 |
(1) Spring (2) Piston (3) Inlet/exhaust valve (4) Spring | |
The air compressor governor operates with the compressor unloader pistons in the air compressor in order to control the air pressure in the system. When the air compressor governor is adjusted, spring (1) will hold the adjustment.
When the air pressure that is supplied by the air compressor increases to the cut-out pressure setting, the air pressure moves piston (2) against the force of spring (4) . Piston (2) moves inlet/exhaust valve (3) in order to open the passage to the compressor unloader mechanism. The air pressure flows through the air compressor governor to the compressor unloader mechanism. The compressor unloader mechanism stops the flow of compressed air to the rest of the system.
When the air pressure that enters the air compressor governor decreases to the minimum cut-in pressure, the force of spring (4) is greater than the air pressure that is acting on piston (2) . Inlet/exhaust valve (3) moves in order to close the passage. This simultaneously opens the exhaust opening of the air compressor governor. The air compressor will send compressed air flow to the air dryer.