Thanks for the video, it helps. The noise you are hearing is a cam follower that has gone bad, you will need to remove the valve cover and inspect the valve train. What happens is that the roller bearings inside one of the followers has come apart. Use a flashlight to help with the inspection, make sure to turn the engine over by hand to check the followers under tension form the cam lobe.
https://www.2carpros.com/articles/engine-seized-test
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Tuesday, April 30th, 2024 AT 11:00 AM