PREVENTIVE MAINTENANCE NOISE AND EMISSION CONTROL
Regional Haul
(R05/10) Y53-6033 – 253 –
Engine Cooling System
• Removing or rendering inoperative the fan clutch.
• Removing the fan shroud.
Engine
• Removing or rendering engine speed governor inop-
erative so as to allow engine speed to exceed manu-
facturer's specifications.
• Modifying ECU parameters.
Exhaust System
• Removing or rendering inoperative exhaust system
components.
Inspection and Maintenance Instructions
The following instructions are based on inspection of the
noise control system at regular intervals.
If, during periodic inspection and maintenance of other
systems and components, it is found that parts of the
noise control system require attention, we recommend
that those parts be inspected at more frequent intervals to
assure adequate maintenance and performance.
Air Intake System
• Do all checks and maintenance procedures listed in
this manual under Engine Air Intake System and Air
Cleaner. See “Air Intake System” on page 196.
• Check the induction tubing, elbow connections,
clamps, brackets, and fasteners for deterioration,
cracks, and security.
• If you find an air leak anywhere between the air
cleaner and the engine, repair that leak immediately.
CAUTION: Air leaks cause excessive noise
and may result in serious damage to the
engine. If you do not repair them the engine
damage will not be covered by your warranty.
Repair all air leaks as soon as you find them.
Exhaust System
• Check for exhaust leaks, which would indicate a leak-
ing manifold gasket; replace gasket if necessary.
• Check cap screws for tightness, including those at the
flanges. Refer to the engine manufacturer's service
manual for proper tightening sequence and torque
values.
