Oil Rail Cleaning Procedure For the C9 Engine
C9 Cylinder Head
Note: Contain any oil and cleaner that will flow from the cylinder and the lines during the following process. Properly dispose of the oil and contaminated cleaner when work is complete.
- Remove fuel injectors. Refer to Disassembly and Assembly for specific machine.
- Install six plugs 9U-7080 Tapered Cap/Plug into the lower injector bores. These will prevent oil, cleaners, and debris from entering the cylinders.
- Remove the plugs from the front and rear of the cylinder head main oil gallery.
- Remove the pressure sensor from the cylinder head. Protect the sensor.
- Using the brake cleaner and long spraying straw in the injector bores flush the passages from the injector bores to the rail.
- Using the brake cleaner and long spraying straw in the injector bores flush out the fuel passages between the injector bores.
- Using the shop vacuum suck out the brake cleaner and debris from the injector bores as needed.
- Using the solvent gun with and without the air hose extension blast mineral spirits into the rail, washing debris out the rear plug hole. If rear plug cannot be removed solvent will have to be sprayed in and then sucked out with the shop vacuum.
Note: The fluid will turn clear as soon as the oil is washed out of the rail but flushing must continue until there are no more shiny metallic particles.
- Continue to repeat steps 5 through 8, squirting the solvent gun into the rail through every hole possible, including the front and rear main gallery plug holes, the sensor hole, and the pump inlet hole. Monitor accumulation of dirty solvent in the cups while spraying solvent, suck out as required. Flush until the mineral spirits and brake cleaner run clear with no shiny metallic particles.
- Using a drop light and small mirror inspect entire rail for debris. If any is found repeat cleaning procedure until rail is completely clean of debris.
- Double check that any fluid in caps has no debris, suck out fluid, remove caps, suck out cylinders.
- Clean and reassemble the oil filter bypass valve.
- Refer to Truck Engine News, SEBD6764, “A New Spring for the Oil Filter Bypass Valve and for the Oil Cooler Bypass Valve is Now in Production”, Service Magazine, SEPD0718, “A New Spring for the Oil Filter Bypass Valve and for the Oil Cooler Bypass Valve is Now in Production” and Engine News, SEBD9329, “A New Spring for the Oil Filter Bypass Valve and for the Oil Cooler Bypass Valve is Now in Production” for the correct selection of the springs for the bypass relief valve and the oil cooler.
- Reassemble engine, using replacement HEUI Pump and Injectors.
- Replace the engine oil and the oil filter. Refer to the Operation and Maintenance Manual for your specific machine to determine refill capacity.