The six rocker arms and eccentrics from one rocker shaft - shown before cleaning.
Two clean rocker arms. Note the numbers 7 and six cast in front of the adjuster sockets: 7 denotes a left hand arm (viewed from the valve end) and 6 a right. Important when re-assembling as they have different off-set angles. Positioning applies to both heads.
The #6 arms also have RR cast into the valve end.
The arms are cross-drilled to supply oil to each end. Beneath the adjuster end there is an angled hole of 0.0315" diameter to drip oil onto the pushrod cup. In the vertical face above the valve pad there is a drilling of approximately 0.015". These holes are easily blocked at the best of times and must be cleared. In an attempt to reduce oil consumption R-R modified the valve end by fitting small felt pad 'filters' which effectively blocked the supply to the valve stem. When cleaning my rocker arms I found that only three arms retained vestiges of these filters; the remnants were like pieces of grit blocking the passages. In an attempt to return a reasonable oil supply to the upper engine these felt strainers were not be replaced during re-assembly.
Following the completion of the rebuild, when the engine was being run in, it was observed that the push rods were not receiving an adequate oil supply as oil was over-feeding the valve stems as well as leaching out through the bushes. Five thin felt pads were inserted into each rocker at the valve-end - it was then found that oil was lubricating the push rods and was still dribbling out over the valve stems.