In addition to the above, I will note that it is very easy to overtighten your adjustment. Getting zero lash is more a "feel" and art than a science! In other words, it is very easy to miss the point at which all the lash is taken up. You certainly don't want to tighten till you cannot turn the push rod with your fingers. As you are tightening the rocker, gently spin and lift the push rod up and down - you can tell you have reached zero lash when you no longer have any up and down play.
Ayuh,.... That's what I
Hate 'bout the shop manual explanations,....
It Ain't the Spin, it's the free movement, 'tween the lifter, 'n rocker,.... Lash,....
I do more pullin', 'n pushin',.. Gently,... than any spinnin' the pushrod,...
'n as for pumped up lifters or not,....
The seat is in the same place, held by the spring,...
There's just atad more resistance to compression full of oil, vs. not havin' ever been run,...
I've lost track of how many posters have shown up here with a new reman that won't start,....
Ya finally get 'em to do a compression test, 'n there ain't any,.... Valves Toooo tight,...
I was always taught that 3/4 to a turn puts the lifter piston in 'bout the middle of it's stroke,...
It's a Hyd. lifter,...... it ain't that Critical a measurement,......
Critical is on a solid lifter motor, ya set lash with feeler gauges,...