6.7 Won't start after changing the fuel filter

I changed the fuel filters on my 2015 6.7 using the Motorcraft filter kit.

I drained the fuel/water separator, removed the housing and filter, cleaned the area, and installed the new filter and o-ring lubed the o-ring with fresh diesel fuel. I hand-tightened until I felt the o-ring engage, then tightened until it stopped.

I also replaced the engine-mounted fuel filter and made sure all fittings were securely connected.

I cycled the key for 30 seconds at a time, repeating this 7 times. After checking for leaks, I cycled it another 3 times just to be safe.

The truck started briefly but then shut off, and I have not tried starting it again. It feels like air is getting in somewhere, but I am unsure where. I have double-checked everything I touched and tightened it all.

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Thanks for the feedback. I initially removed it and coated the outside with oil, but I should have taken off the O-ring completely and coated the entire component.

Has anyone experienced problems with the drain valve letting in air? While draining the housing, I noticed fuel leaking from the handle, which has always been difficult to turn.

What are the odds that the high-pressure pump might be damaged? The truck only ran for about two seconds.

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After I took my off again, I acted in such manner. removed the o-ring entirely and applied oil to it. I eventually got my truck to start and run, though it was a pain.

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When your pump refused to start, did it make a noise? My own is much louder now than it was previously.

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The noise is due to the pump cavitating and drawing in air. While many people use oil, I prefer applying a light coating of grease as a diesel mechanic. This approach helps prevent the O-ring from tearing and ensures that the filter is fully seated.

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Priming it might occasionally be a pain in the ass. You cycled the key a number of times without actually starting it.

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I keep cycling to prime till the system stops making noise. After a water drop or inspection, my 2022 goes through roughly 12 cycles.