Thread: 4 year old rebuild in Corvette - now tapping or knocking...leaking oil

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Had this happen years ago, I had a lifter ticking I would retighten it and it would start again, it ended up that one of the pressed in rocker studs was pulling out with the higher valve spring pressure and bigger cam lobes, ended up having to put in screw in studs. Not that this is your problem but "This happened too me"! Check and see if the stud length on the rocker nuts protrude all about the same and ones not lifting. Also Welcome!

Originally Posted by Matthyj

Had this happen years ago, I had a lifter ticking I would retighten it and it would start again, it ended up that one of the pressed in rocker studs was pulling out with the higher valve spring pressure and bigger cam lobes, ended up having to put in screw in studs. Not that this is your problem but "This happened too me"! Check and see if the stud length on the rocker nuts protrude all about the same and ones not lifting. Also Welcome!

Matt's suggestion is great! I had forgotten, but I've seen that before, too, where a rocker stud was pulling out of the head with the dynamic loading and higher spring pressures. Adjust it, and a few days it's ticking again. Pinning the studs, or better yet, threading the head for screw in studs fixed it!

That's what I'm wondering....if the internals of the lifter are damaged. That would account for the rocker not oiling.

Push Rod was turning though, so I'm hoping the lobe is ok. Still going to take oil filter apart and check to see if I can see metal. Didn't see any obvious flakes when I drained it.

I can still get these same lifters (Edelbrock) from Summit Racing, so I could get one, install it, and break it in....see if that fixes it. Getting the cam out of a Corvette is near impossible without pulling the engine. I do remember that