Replacing Dt466e Injectors requires attention to detail to prevent engine damage. Injector O-rings should always be replaced with new ones during injector removal. These are essentially one-use parts, especially after prolonged exposure to heat and pressure. Reusing O-rings risks leaks due to potential damage or slight rotation during removal, compromising the 3000 PSI seal against the high-pressure oil pump (HPOP).
Before installing new injectors, ensure all fuel and oil are cleared from the cylinders. While residual fuel might seep past the rings into the oil pan, oil will pool, leading to hydrolock and engine damage upon starting. The mechanically driven HPOP, even at minimum pressure regulated by the injection pressure regulator (IPR), will pump oil into the cylinders with injectors removed.
To prevent this, after installing new injectors, manually rotate the engine four full turns. This laborious process is crucial for safely clearing the cylinders. Hand-cranking allows you to physically feel any resistance from hydrolock, indicating trapped oil. This method also allows pressurized oil to escape past the piston rings on the exhaust stroke, preventing damage.
Furthermore, an oil change is mandatory after this procedure. Whether you choose to replace the bearings depends on the engine’s condition. Signs of worn bearings, such as low hot oil pressure or unusual noise, warrant bearing replacement. However, if no such symptoms exist and you’re not performing a full rebuild or in-frame overhaul, bearing replacement might not be necessary. Changing the oil ensures any contaminants pushed into the oil pan during the process are removed, protecting the engine’s longevity.
