Diagnosing Air System Malfunctions; Air Flow Restriction Results In Excess Smoke And Low Power - Dodge D250 1990 Service Manual

Exhaust System and Intake Manifold
DODGE Turbo Diesel
Air System
Page 11-3
Diagnosing Air System Malfunctions
The correct amount of clean air to the cylinders is required for
good performance. As discussed earlier in System Air Flow,
ingested dust and dirt will damage the engine cylinders. Dust
and dirt can also damage the valve stems and guides. Larger
debris can damage the blades of the turbocharger.
Air Flow Restriction Results in Excess Smoke
and Low Power
Restriction increases as the filter removes contaminants from
the intake air. Restricted air flow changes the air-to-fuel ratio,
reducing power and increasing smoke from the engine. Verify
that the air cleaner is being maintained correctly.
Debris drawn Into the air suction side can damage the
compressor blades causing an imbalance resulting in a bearing
failure. To verify a bearing failure or damaged compressor,
remove the intake and exhaust piping and check for contact.
The rotor assembly must rotate freely. Measurement of axial
and radial clearance is described in this Section.