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Posting these questions concerning the roller rocker shafts for a 320 engine in a '37 Super Eight. In removing the rocker arm assemblies two questions have arisen. Before going to each question I'll include a little of what I understand about the parts in question.

1) The hollow shafts on which the rockers rotate have eight chamfered oil feed holes in each to provide oil to the rockers on each shaft. But...there is also one separate hole on each shaft, 180 degrees from the other eight holes. This separate hole is towards one end of the shaft. It is to be noted that oil enters through the hollow end of each shaft, travels the length of the shaft and provides oil to the rockers from the eight oiling holes. Finally the question. Which end of the shaft should the separate hole be orientated to? The oil feed end or the other end?

2) The second question concerns the "fixing" of the hollow shaft. As they now are, the hollow shafts could move backwards/forwards because there is room for them to do so. So, the question is, should there be anything to fix/hold the shafts in position to prevent any backwards/forwards movement?

Edit - click on each pic to obtain a larger image.

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Mal, I had plenty of these apart years ago and probably did know the answer to #1 at one time, but it was just too long ago. But with regard to #2, the position of the rocker arms themselves is fixed by the cover casting so they align with the tappets and thus they are not free to move fore and aft. But if the shaft itself does, then then oil holes will not always align with the feed hole to the pin and roller. So the shaft must be fixed in a position where the 8 holes in the shaft align with the 8 holes in the rocker arms. This would also align the single oil hole on the backside of the shaft. Perhaps there were shim washers at each end beneath the endcap screws to position the shafts within the housing?

If you go back to the service letters, there is a bulletin on how to install these. As I recall it is backwards of what you might think. But without the actual note in front of me I can't quote with precision.

O_D, Thanks for your response.

And Tim, I'm working my way through the Service Letters on site here. Have perused '33, '34 and '36 and presently working through '37 but haven't come across anything yet. Additionally there are some SL's that are missing or partial copies only.

Mal, I have all the 33-34 Service Letters and many earlier ones back to the 7th series, and have browsed them all for the reference Tim Cole mentioned, without success. I found the one on the replacement of the stamped with forged rocker levers but that's not relevant at all; I did find the attached - it's not exactly on-point but here it is, for what it's worth.

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Dave, thanks for saving these failing eyes. I was beginning to wonder whether I'd find anything at all relevant in all those pages. At times, when looking, I was distracted by many other interesting matters on diverse topics. My Packard education continues.