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 head casting 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 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.
2. Plug in the cylinder block heater to warm coolant.
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 tank.
NOTE: Engines are equipped with a fuel pressure test valve in the form of either a Shrader valve or a
diagnostic coupling.
4. Pressurize fuel rail with air from the fuel pressure test valve on the intake manifold to 550 kPa to 690 kPa (80 psi to 100 psi) using the fuel line test adapter. Observe deaeration tank for air bubbles.
• If air bubbles appear in deaeration tank, do step 5.
• If air bubbles do not appear in deaeration tank, do step 6.
5. Remove all injectors and inspect O-rings and injector sleeves for damage.
• If any injector O-ring or injector sleeve appears damaged, clean the injector and replace O-rings or injector sleeves. Test the system again. Do step 4.
• If injector O-rings or injector cups are not damaged, do step 6.
6. Remove, inspect, and pressurize the cylinder head following the procedure in the Engine Service Manual.
