How do hydraulic flat tappet lifters fail?

I think (I hope) we’ll find some answers when I pull the cam and lifters. Drained the oil today and it was very, very clean. I’m going to cut into the filter and see what it looks like, and check the rod and main bearings (at least a few) to ensure they’re in good shape.

When I pulled the valve cover, I saw the #1 intake pushrod shifted to the side. Here you can see the divot it made in the rocker. And yes, I have a new rocker to replace it! :lol:View attachment 1715614237
Are our rockers on the shaft correct? There are lefts and rights.