Dave,
I have seen your suggestion about the lifters. I haven't figured out how they could be at fault. It seems that if they are collapsed 100%, they are now solid lifters. I don't think a fully collapsed lifter can pump back up if it is adjusted "as a solid".
The minimal oil pressure only has to fill the lifter. The little disc valve holds the pressure in the lifter.
Under the worst case scenario, maybe the lifter was partially collapsed, adjusted to 1 turn after quiet, then pumped up and bottomed the valve spring, breaking the rocker arm. I don't think that could happen, mechanically speaking.
It appears the problem is solved by replacing the broken rocker arms, so one would assume that they were the problem.
I have my beach towel handy, I might be all wet too!
Stuart
