International DT466 – ENGINE SYMPTOMS DIAGNOSTICS – Priming Fuel System - Diesel Engines Troubleshooting (2025)

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CAUTION: Do not add fuel to the fuel filter header.
This can add contaminates to the fuel.

Tools
• Fuel Pressure Gauge
• Fuel pressure test adapter
• Fuel Test Fitting
• Fuel/Oil Pressure Test Coupler
• 1 to 5 gallon bucket

If the engine runs out of fuel, do the following:
1. Set parking brake and place transmission control lever to NEUTRAL or PARK.
2. Verify that there is at least 15 liters to 19 liters (4 gallons to 5 gallons) of fuel in the tank.

NOTE: If your vehicle is equipped with dual fuel tanks, fill each tank with 15 liters to 19 liters (4 gallons to 5 gallons) of fuel.
3. Unlock the fuel primer pump assembly by turning the knob counter-clockwise.
4. Fill the fuel filter header and fuel rail by pumping the fuel primer pump.
5. Pump the system until enough pressure is built up. Typically, 20 to 30 pumps will build enough pressure. At this point, the pump plunger will become difficult to pump. Make sure the pump plunger is pushed in when finished. It is not necessary to lock the fuel primer knob at this time.
• If the pump is working correctly and the pressure is built up, do step 11.
• If the pump plunger does not pump on the first attempt, the fuel system may be full of compressed air. Do step 6.
• If little pressure is felt after pushing the knob of the fuel primer pump several times, air must be bled from the fuel rail. Do step 8.

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.

6. Place either a shop rag or suitable container under the fuel pressure test valve.
NOTE: It is recommended to use the Fuel Pressure Test Adapter to avoid bending the needle in the Shrader valve. The Fuel Pressure Test Adapter is part of Fuel Pressure Test Kit ZTSE4657.

7. Depress the fuel pressure test valve center section.
• If air is released, and you can now pump the primer hand pump, go to “Aerated Fuel” (page 104) in this section.
• If unable to work the pump after releasing pressure from the fuel test valve, repair the fuel pump primer.

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.
8. Install the Fuel Pressure Gauge with shut-off valve into the test port at the front of the intake manifold.
Run the discharge hose into a bucket.
9. Open the shut-off valve. Pump the fuel primer pump knob until a steady stream of fuel flows out of the clear hose.
• If fuel has air bubbles, go to “Aerated Fuel” (page 104) in this section.
• If fuel flows without air bubbles, close shut-off valve. Do step 10.
10. Pump the fuel primer pump again to build pressure in the system. Lock down the knob.
11. Start the engine.
12. If the engine does not start in 20 seconds, repeat the priming procedure.
13. Once the engine starts, let it run for five to 10 seconds, then shut-off the engine. Turn the fuel primer pump knob clockwise to lock in place.
14. Remove fuel pressure test fitting (if used) and dispose of any fuel in correct container clearly marked DIESEL FUEL according to local regulations.