Originally Posted by kwillymac

About two years ago my friend bought a 540 BBC from Scoggin Dickey. He ran the motor for about a year and a half and then the Roller lifter broke. We took the motor apart and found that all the pushrods on the intake or Exhaust (Don't remember which) side were worn down on the rocker side. They were shiny and coming almost to a point.

I do remember that the valve lash would loosen about every week. Sometimes being as much as .025 off. The motor had Dart Pro One 335 cc CNC Heads on it. It also had a stud girdle and poly locks. No matter what the lash would loosen up. Usually an indicator of a cam problem. This was a billet Roller cam.

My guess on what could have happened was that the pushrods may have been the wrong length. When the lash loosened the roller lifter started bouncing on the lobe and finally broke. This is of course a guess. Any opinions on this?