I have my motor out and on a stand to do some work. I installed GT-40 heads and 1.7 Crane pedestal rockers over the weekend. Before doing this, I had removed the hydraulic roller lifters, soaked them in mineral spirits for a few hours, blew them dry with compressed air, and then soaked them in fresh oil for a week. I put the lifters back in the block, and then a few hours later after mounting the heads, I torqued the rocker arms to spec. All rockers hit recommend spec within 3/8 to 3/4 of a turn. Everything good so far.
Afterwards, I happened to push down on the pushrod side of one of the rockers. With very little force, the lifter compressed about 1/4". I'm talking very little pressure from just my finger. A couple of others ones felt like this too. Several hours later, I came back, turned the engine over by hand a few times, and checked them all again. Most of the lifters seemed to have bled down and could be compressed by pushing on the rocker arm with my thumb, but they were not as soft as those first 3. Several lifters were still rock hard.
So, here is the question - is it normal for lifters to bleed down that fast and be that soft? Also, is it normal for some lifters to stay "pumped up" that long?