6 PERFORMANCE DIAGNOSTICS 229
7. Intake Restriction
Figure 297
Purpose
To check for restriction in the air intake system likely
to cause engine performance problems.
NOTE: High intake or exhaust restriction can cause a
large amount of black smoke.
Tools
• Gauge Bar (magnehelic)
• Test line
Procedure
WARNING: To avoid serious personal injury,
possible death or damage to the engine or
vehicle, read all safety instructi on s in the “Safety
Information” section of this manual.
1. Inspect the following parts for restriction, damage
or incorrect installation:
•Airfi lter inlet and ducting (includes hood)
• Air inlet hoses and clamps
•Airfilter housing, filter element, and gaskets
• Chassis mounted CAC and piping
•Airfilter restriction indicator or gauge
Figure 298 Low restriction
Figure 299 High rest
riction
NOTE: Intake restr
iction should be below 25 in H
2
O.
When the filter elem
ent reaches maximum allowable
restriction, the
yellow indicator will reach the top of
window and autom
atically loc k in this positio n.
EGES-270-1
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Follow all warnings, cautions, and notes.
©August 2008 Navistar, Inc.
To Next Page
Loading...
Need help?
General