Karl, Adjusting hydraulic lifters by rotating the pushrod only works if your lifter is pumped up with oil, unless you have the side cover off and can visually see the lifter cup start to rotate as you tighten down the rocker while spinning the pushrod. Otherwise if there is no oil in the lifter or the lifter has bled down, you will bottom out the plunger of the hydraulic lifter which you don't want to do, then you add another 1/4 turn then guess what? You engine will not start because you have removed all the hydraulic action of the lifter. Either that has happened or I'm betting if you have a solid lifter and you must set it up with clearance between the rocker and valve or else it will not run either. Pull all the pushrods and check them for straightness, then you will be able to see what lifter you have, it will be obvious. In my opinion you will bend those long rods before you hurt anything else. My .02
Steve

Last edited by sstock; 11/18/2014 4:56 PM.
1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration