106
Figure 117 Fuel Pressure Gauge to fuel pressure
test adapter
3. Connect Fuel Pressure Gauge with shut-off valve
and clear 3/8" diameter hose to test valve.
4. Route the clear hose into a drain pan.
5. Start or crank the engine for 20 seconds. Measure
fuel pressure with the shut-off valve closed. Open
the shut-off valve to check for aeration.
NOTE: Breaking any fuel system joint will induce
air into the fuel system. The air should pass in a
short period of time. As fuel pressure is relieved, a
steady stream of fuel without air bubbles indicates
the fuel is not aerated.
•
If fuel pressure is in specification and fuel is
not aerated, do not continue with this test.
•
If the fuel is aerated, 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.
Alternate Fuel Source Supply to Fuel Pump
Figure 118 Fuel supply line
1. Remove fuel pump supply line.
Figure 119 Fuel test line