This may not be a very "advanced" topic, but nonetheless it's something that a lot of people struggle with on this board. I was hopin we could find a real definite proper way of going about finding zero lash. Spinning, jiggling, whatever. ive tryed the spinning of the pushrod till you first feel drag, and ive tryed doing an up and down motion with the pushsrod, till theres no slack, not paying attention to the spinning at all.

Which way is the correct way to achieve zero lash, the first time every time?

 

Back the rocker off until it's noticably loose. Wait a few seconds for the lifter to unload. I jiggle the pushrod until it stops rattling. Tighten the rocker nut 1/2 turn more. That gives you the required .030" preload inside the hydraulic lifter. Because of how a hydraulic lifter works, you can tighten it down then wait and it will seem like you're at zero lash again. Don't tighten it down more after that.

It you really want to get precise you can use a dial gauge and a .0015 feeler gauge. Put the feeler gauge on the valve stem and adjust the rocker until a slight drag is felt. Use the dial gauge to preload the lifter .030"

 

and from what I'm told it is different for roller rockers than the stamped pieces, up and down for rollers and twist for stamped from what I've gathered

 

I've never liked the twist method. I twist them to zero lash, adjust the rocker and can still twist the pushrod.