4 ENGIN E SY M PTOMS DIAGNOSTICS 115
Fuel in Coolant
Symptom
Coolant contaminated with diesel fuel will have a
diesel fuel odor.
Cause
• Leaking or cracked injector sleeve with injector
O-ring failure
• Cracked or porous h ea d c asting in fuel rail
cross-drillings.
Tools
• Regulated compressed air
• Fuel Test Fitting
• Fuel/Oil Pressure Test Coupler
• Cylinder head test plate
• Water supply housing pressure adapter
• Thermostat opening pressure adapter (cylinder
head)
Procedure
1. Verify coolant contamination.
• Check for diesel fuel odor in coolant.
• Coolant may be discolored if diesel fuel is
present.
CAUTION: Be sure to place a rag o r suitab le
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. N ever dispose of engine fuel
by putting it in the trash, pouring on the ground,
in the sewers, in streams, or bodies of water.
2. Plug in the cylinder block heater to warm coolant.
WARNING: To avoid serious personal injury,
possible death and damage to the engine:
• Always allow the engine to cool for 15
minutes.
• Wrap a thick cloth around the cap.
• Loosen cap slowly a quarter to half turn.
• Pauseforamomenttoavoidwaterorsteam
scalding.
• Contin ue to turn th e cap and remove.
• Never add cold coolant to a hot engine. This
can result in a cracked cylinder head or
crankcase.
• Never use water as a coolant substitute.
Figure 129 Deaeration tank fill position
1. Deaeration tank cap
2. Deaeration tank
3. MAXIMUM coolant level mark
4. ADD coolant level mark
3. Remove cap from deaeration tank and fill with
coolant to a level above the deaeration inlet line
to tan k .
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.