IC Bus Gasoline CE Series, Operation And Maintenance Manual

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Maintenance Instructions
High Restriction Reading
Possible Causes Explanation
Plugged elements Ultra fine particles are difficult to remove and cleaning may not sufficiently lower restriction.
Plugged inner element (if equipped) Replace inner element.
Plugged inlet screens or ducts Check system upstream from restriction tap for debris, damage, or improper installation.
Heavy snow or rain
Temporary high restriction can occur during a rain or snow storm and it disappears after drying out.
Cold air may be so dense that high restriction may not reduce engine power before elements are
damaged from high vacuum. If gauge is locked up at RED zone, check elements for damage.
Radiator Core Inspection and Cleaning
With the engine OFF, visually inspect the radiator core assembly
for debris and clogging of external fins. Prior to engine operation,
remove any debris blocking the core.
Cooling System
WARNING
To prevent personal injury and / or death,
or property damage, do the following when
removing radiator or deaeration cap:
• Allow the engine to cool.
• Wrap a thick cloth around pressure cap.
• Partially unscrew pressure cap slowly while
firmly holding cap down, then pause to allow
pressure to release.
• When system pressure is released, fully
unscrew pressure cap while continuing to hold
cap down. Slowly release downward pressure
from pressure cap.
• Remove cap.
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