Engine
90
AIR INTAKE SySTEM
The air intake system routes the fresh outside air through the filter and into the turbocharger air intake.
Parts of the air intake system include the air cleaner assembly and the piping, hoses, and hardware that
connect it to the engine. The air cleaner contains a dry, replaceable filter element which should be re
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placed when the red marker in the air restriction indicator window pops up. After replacing the air cleaner
filter element, reset the air restriction indicator by depressing the button at the bottom of the unit.
The air cleaner system should be inspected at intervals specified in the “Maintenance Schedule” in the
Preventive Maintenance section of this manual. It is recommended that a schedule be established for
replacing the air cleaner filter element based on manometer readings taken at scheduled intervals.
Air Intake Inspection
It is not necessary to disassemble the air cleaner for inspection.
1. Inspect the air cleaner body for cracks and loose mounting bolts or nuts.
2. Check to be sure the restriction indicator is not loose or damaged.
3. Check the air induction hose clamps for tightness. Tighten loose clamps and replace clamps which
are damaged or broken.
4. Inspect the air induction hoses for holes or leaks.
5. Check for loose, broken, or missing mounting brackets.
Air Cleaner Troubleshooting
Attempt to determine the exact nature of the problem and its causes. If the trouble involves the air clean-
er, it will fall into one of two types:
• Those which result in short element life.
• Those which allow dust to enter the engine.
If the problem is with the air cleaner, follow the steps listed below.
Short Element Life
1. Check to make sure the inlet is located away from heavy dust concentrations.
2. Check the inlet location to be sure that exhaust gasses are directed above and away from the air
cleaner inlet. Soot from exhaust is a prime enemy of paper filters.
3. Check the air supply to the air cleaner inlet. It must be unrestricted.
4. Check to make sure the air cleaner element was new or properly cleaned when installed.
5. Check the clean air ducting after the air cleaner to be certain it is unrestricted.
6. Check the service indicator for damage, working lockup function, and correct calibration.
7. Low pre-cleaner efficiency will cause short element life. Low pre-cleaning efficiency can be
caused by:
a. Leaking dust cup to air cleaner body joint. The cup must seal 360° around the air cleaner.
b. Plugging or buildup in the vanes of the pre-cleaner.
c. Damage to the pre-cleaning section of the air cleaner.
Summary of Contents for LOW FLOOR
Page 18: ...Specifications 18...
Page 58: ...Preventive Maintenance 58...
Page 110: ...Engine 110...
Page 138: ...Transmission Driveline Rear Axle 138...
Page 182: ...Suspension 182...
Page 260: ...Air System 260...
Page 420: ...Electrical System 420 Deutsch DT Series Connectors...
Page 421: ...Electrical System 421...
Page 422: ...Electrical System 422 Deutsch HD 10 Series Connectors...
Page 423: ...Electrical System 423...
Page 424: ...Electrical System 424 Deutsch HD 30 Series Connectors...
Page 425: ...Electrical System 425...
Page 442: ...Heating Air Conditioning 442...
Page 492: ...Body and Interior 492 Figure 11 33 USSC Seat Assembly...
Page 493: ...Body and Interior 493 Figure 11 34 USSC Seat Suspension Assembly...
Page 495: ...Body and Interior 495 Figure 11 37 Seat Air Connections...