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Home >> Hummer >> 2003 >> H2 >> Repair and Diagnosis >> External Pages >> Different car >> Section 45 (Engine Controls - Basic Diagnostic Procedures - 6.6L Diesel) >> Fuel Systems >> Fuel System Priming >> Priming Procedures
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Priming Procedures

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Prior to priming the engine, ensure that there is fuel in fuel tank, fuel filter has been installed and properly tightened, fuel lines are properly connected, fuel filter is cool to the touch, and any dirt or debris is removed from fuel filter head and vent valve.
  2. Open vent valve, located on top of fuel filter housing, by turning the screw counterclockwise several full turns. See Figure.
  3. Operate the priming pump until a small amount of fuel seeps from the vent valve. Allow pump to return upwards between pumps. When fuel is present, the filter is full of fuel and system should be primed.
  4. Close the vent valve.
  5. Clean any fuel which accumulated on the fuel filter.
  6. Start the engine and allow it to idle for a few minutes.
  7. Check filter for leaks.
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