Aerated Fuel; Aerated Fuel Inspection - Navistar International DT 466 Diagnostic/Troubleshooting Manual

104

Aerated Fuel

Symptom
Fuel aeration will exhibit one or more of the following
characteristics:
• Engine stall during operation
• White to black smoke during cranking
• Rough running engine
• Extended engine crank time (hard start)
• Fuel pressure slow to build while cranking
• Excessive fuel pressure while cranking
• Pulsating fuel pressure during crank or engine
running at idle.
• Difficulty priming fuel system
Cause
• Leaks in fuel supply to fuel pump
• Loose fuel injector hold down
• Missing/damaged stainless steel injector gasket
Tools
• Fuel Pressure Test Gauge
• 1 to 5 gallon bucket
• Fuel pump supply line
• Fuel filter housing supply line fitting (Part No.
3533425C2)
• Fuel Pressure Test Adapter
• Fuel/Oil Pressure Test Coupler

Aerated Fuel Inspection

NOTE: If directed to this procedure from "Hard Start
and No Start Diagnostics" section, go to "Alternate
Fuel Source Supply to Fuel Pump" (page 106) in this
section.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
4 ENGINE SYMPTOMS DIAGNOSTICS
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
CAUTION: Be sure to place a rag or suitable container
under the fuel pressure test valve when bleeding the
fuel rail. Dispose of fuel in a correct container clearly
marked DIESEL FUEL according to local regulations.
NOTE: Engine fuel can be a threat to the environment.
Never dispose of engine fuel by putting it in the trash,
pouring on the ground, in the sewers, in streams, or
bodies of water.
Figure 112 Shrader valve assembly
1. Valve
2. Center stem
Figure 113 Diagnostic coupling
1. Valve
2. Center section