How to open up rocker arm oil passages.

The round band that goes through the rocker part of the rocker arm can turn inside the rocker arm over time. It has only a slight press fit and is easily turned if you put it in a vise. I've noticed that when they turn, the oil hole becomes misaligned and can prevent oil from passing through it. It's easy to spot by looking at the oil hole inside of the rocker and seeing if it lines up. Many people that have high spring pressures put a small weld bead on the sleeve/rocker junction to prevent it from turning or moving under increased spring pressures...