Cylinder Head - Oil Flow through Rocker Arms

Just been testing the oil flow through the Cylinder Head Rocker Spindles, after fitting my new one piece Spindle Covers. I have no issue seeing oil migrate along the spindle and out the ends where the thrust and spring washers are, but don't see any oil come out the end of the Rocker Arm where the Push Rods engage. Am I correct to assume that as Norton went to the trouble of drilling a hole connecting the Spindle Shaft bore with this point that it was their intention to lubricate it. I have fitted the Rocker Spindles with their flats pointing away from the cylinder heads center as per manual, but it occurred to me that perhaps if the flats were installed in the opposite direction I could get oil flow the the Push Rod / Rocker Arm engagement points. Can anyone enlighten me on this oil flow and as to why the Rocker Spindle Shafts need the flats orientated away from the center.

Crockett23 said:

Just been testing the oil flow through the Cylinder Head Rocker Spindles, after fitting my new one piece Spindle Covers. I have no issue seeing oil migrate along the spindle and out the ends where the thrust and spring washers are, but don't see any oil come out the end of the Rocker Arm where the Push Rods engage. Am I correct to assume that as Norton went to the trouble of drilling a hole connecting the Spindle Shaft bore with this point that it was their intention to lubricate it. I have fitted the Rocker Spindles with their flats pointing away from the cylinder heads center as per manual, but it occurred to me that perhaps if the flats were installed in the opposite direction I could get oil flow the the Push Rod / Rocker Arm engagement points. Can anyone enlighten me on this oil flow and as to why the Rocker Spindle Shafts need the flats orientated away from the center.
View attachment 104443View attachment 104446

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Not authoritative: To reduce over oiling.

Crockett23 said:

Can anyone enlighten me on this oil flow and as to why the Rocker Spindle Shafts need the flats orientated away from the center.

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The spindle holes and rocker drillings are on opposing sides so the oil has to flow around the spindle thus lubricating it and the rocker in the process to reach the rocker drilling.
If the spindle holes are aligned with the rocker drillings (so spindle holes facing inward) the flow would then be unrestricted resulting in a loss of oil pressure not just to the rocker gear but also to the big end bearings.

L.A.B. said:

The spindle holes and rocker drillings are on opposing sides so the oil has to flow around the spindle thus lubricating it and the rocker in the process to reach the rocker drilling.
If the spindle holes are aligned with the rocker drillings (so spindle holes facing inward) the flow would then be unrestricted resulting in a loss of oil pressure not just to the rocker gear but also to the big end bearings.

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So with this arrangement, it sounds like there can be a fair amount of variance in spindle orientation as long as correctly facing flats to outside. End plate tangs do not need to precisely hold the spindle in a particular angle, just set some restriction on it?

Tornado said:

So with this arrangement, it sounds like there can be a fair amount of variance in spindle orientation as long as correctly facing flats to outside. End plate tangs do not need to precisely hold the spindle in a particular angle, just set some restriction on it?

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With the inner rocker end plates with the tangs in place then there shouldn't be much variance.

L.A.B. said:

With the inner rocker end plates with the tangs in place then there shouldn't be much variance.

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But the tang's don't seem to fit & to hold the spindle positively...fair bit of slop exists, at least that's how I recall them on mine. As long as flats remain generally facing to outside of head, then oil should reach the rockers as Mr. Norton intended if as you said earlier.

Tornado said:

But the tang's don't seem to fit & to hold the spindle positively...fair bit of slop exists, at least that's how I recall them on mine. As long as flats remain generally facing to outside of head, then oil should reach the rockers as Mr. Norton intended if as you said earlier.

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Yes, I expect a few degrees, either way, probably makes no difference.

On the dunstall commando the oil feed to the head was reduced with an inline 20 thou jet I believe

Tornado said:

But the tang's don't seem to fit & to hold the spindle positively...fair bit of slop exists, at least that's how I recall them on mine. As long as flats remain generally facing to outside of head, then oil should reach the rockers as Mr. Norton intended if as you said earlier.

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One caution: If the tangs are narrow and the spindle is too far counterclockwise the oil flow to that spindle can be shut off completely. Even with the slots in the spindles horizontal, the hole where the oil enters each spindle slot is partly blocked.

L.A.B. said:

The spindle holes and rocker drillings are on opposing sides so the oil has to flow around the spindle thus lubricating it and the rocker in the process to reach the rocker drilling.
If the spindle holes are aligned with the rocker drillings (so spindle holes facing inward) the flow would then be unrestricted resulting in a loss of oil pressure not just to the rocker gear but also to the big end bearings.

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I must admit I thought probably this was the case, however when I bench test (just the head assy.) and try to pressure feed oil to the ends of the rocker arms / push rod I am unsuccessful, so I can only assume that the fast action of the rocker arms in a running engine helps pump the oil through to the push rod ends. I was diligent to ensure the oil passages to these point were clear and I will apply assembly oil to these points for start up, and hope I get flow!

Crockett23 said:

I can only assume that the fast action of the rocker arms in a running engine helps pump the oil through to the push rod ends. I was diligent to ensure the oil passages to these point were clear and I will apply assembly oil to these points for start up, and hope I get flow!

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That probably is what happens or there'd have been a lot of worn-out rocker ball ends from eng. 116372 if it did not.