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International DT466 – ENGINE SYMPTOMS DIAGNOSTICS – Fuel in Lube Oil

Symptom
Oil contaminated with diesel fuel will cause the oil level in engine to increase.

Cause
• Leaking fuel injector or injector O-ring (A leaking injector sleeve or injector tip could cause contaminated engine        oil, but would most likely be identified as a performance problem.)
• Cracked or porous cylinder head casting in fuel rail area cross-drillings

Tools
• 2 oz of fuel dye
• UV Leak Detection Kit (black light)
• Fuel pressure gauge kit
• Fuel pressure test adapter
• Fuel/Oil Pressure Test Coupler
• 1 to 5 gallon bucket
• Inspection mirror

Procedure
NOTE: The black light requires warm-up time. Turn on the black light
1. Verify oil contamination.
NOTE: Other issues that may contribute to fuel dilution beside fuel injectors, include the following:
• Hard starting
• Running rich (strong fuel odor)
• Valve related issue

If the engine is mechanically sound and the oil has been changed, diagnose for fuel in the oil with dye.

2. Remove the fuel filter housing cap.
NOTE: If the fuel filter housing cap is out of the system for an extended time, the O-ring will swell and needs to be      replaced.
3. Add 2 oz fuel dye to the fuel filter housing.
NOTE: Use only recommended dye, manufactured by Balkamp, Inc., available at local NAPA Auto Parts stores,            part number 765-2661.
4. Install the fuel filter housing cap.

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.

NOTE: Engines are equipped with a fuel pressure test valve in the form of either a Shrader valve or a
diagnostic coupling.

NOTE: If the engine is equipped with a Shrader valve, use the Fuel Pressure Test Adapter.

NOTE: If the engine is equipped with a diagnostic coupling, adapt the Fuel/Oil Pressure Test Coupler to
the Fuel Pressure Gauge.

5. Connect a fuel pressure gauge with shut-off valve and clear 3/8” diameter hose to test valve.
6. Route the clear hose into a drain pan.
7. Open the gauge setup shut-off valve
8. Shine the black light at the fuel pressure gauge clear line. The dyed fuel will have a yellow-green fluorescent glow.
9. Using the priming pump, purge the fuel until the dyed fuel begins to flow from the pressure gauge clear hose.

10. Close the shut-off valve.
11. Remove the valve cover following the procedure in the Engine Service Manual.
12. Start and run the engine at low idle for 3 to 5 minutes.

13. While the engine is running, use the black light to inspect for yellow-green streams of dye running between the            valve spring seats at each injector. A small mirror can aid in hard to reach areas.

Inspection should take no longer than 5 minutes. Because disbursement of dye in the fuel, the amount of dye seen does not indicate severity of failure, only that a failure exists.

NOTE: If no dye or leak is found after running engine, verify there is fuel dilution issue by oil analysis or observing an oil level increase.
• If a leak is found, turn off the engine. Do steps 14 through 17.
• If a leak is not found, turn off the engine. Continue with step 18.

14. Remove the high-pressure oil rail following the procedure in the Engine Service Manual.
15. Inspect remaining injectors for leaks. Failed injectors will have a solid yellow-green color around the intensifier          body area (weep hole).
16. Relieve the pressure in the fuel system to avoid further contamination of oil.

17. Replace leaking fuel injector following the procedure in the Engine Service Manual.

NOTE: If a set (six) of injectors must be replaced, contact International® Technical Services to start a case file.
18. Remove the high-pressure oil rail following the procedure in the Engine Service Manual.
19. Use the black light to inspect between each injector and hold-down clamp. Do not remove the injectors.
• If a leak is found, do steps 20 and 21.
• If no leak is found, do steps 22 through 24.
20. Relieve the pressure in the fuel system to avoid further contamination of oil.
21. Replace leaking fuel injector following the procedure in the Engine Service Manual.

NOTE: If a set of injectors (six) must be replaced, contact International® Technical Services to start a case file.
22. Relieve the pressure in the fuel system to avoid further contamination of oil.

23. Remove each injector (one at a time) following the procedure in the Engine Service Manual. Hold each fuel                   injector over their respective injector opening for several seconds to allow fuel to drain from injector. Inspect               each injector.
24. Replace leaking fuel injector following the procedure in the Engine Service Manual.

NOTE: If a set of injectors (six) must be replaced, contact International® Technical Services to start a case file.