Atlas Rocker Spindles

In the high pressure system (rocker oil fee to the sides of the head):

If not facing away from center too much oil will be in the head all the time and especially the intake side will be flooded with oil.

I appreciate and agree with your thinking but since the drainage is poor, especially in the intake side, over oiling is a problem. By the same token, the holes through the head that deliver oil to the slots in the end of the spindles do not line up well - "fix" that and you'll also be over oiling.
So my Atlas feeds from the top of the head, has a 6 start pump, and originates from the crankcase... so it also is high pressure as I understand it and as Slick has said the plain ( no flats ) spindles that I have should all have the oil hole facing the valves. Correct?
 
So my Atlas feeds from the top of the head, has a 6 start pump, and originates from the crankcase... so it also is high pressure as I understand it and as Slick has said the plain ( no flats ) spindles that I have should all have the oil hole facing the valves. Correct?
I should have stayed out of it. I know almost nothing about pre-Commando. I was just trying explain why the feed was away from the hole in the rocker.

L.A.B provided much more info about the "flats". The flats I'm talking about have the oil hole in them and the spindles are not scrolled. I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

In fact, I have an Atlas head like that looking for a home as I'll never have a use for it!
 
The flats I'm talking about have the oil hole in them and the spindles are not scrolled.

Early high pressure spindles apparently had no flats only the oil hole. This type is no longer available.
Later type.

I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

The high pressure rocker feed was introduced from 116372 (during 1966) so before Commando (and before the side feeds).
 
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The high pressure rocker feed was introduced from 116372 (during 1966) so before Commando (and before the side feeds).
OK, good to know. Is there a definitive place that talks about the combinations of spindles, pressures, feed locaitons, etc.? If not, could you be convinced to make one and put it in resources?

Some of the Commando heads I work on have them wrong so I know it's confusing to people even though the Commando workshop manuals are clear.
 
Is there a definitive place that talks about the combinations of spindles, pressures, feed locaitons, etc.?

I don't know although it has been discussed before. If 116372 or later then it should be high pressure regardless of the head feed position and have unscrolled spindles.

If not, could you be convinced to make one and put it in resources?

No, as there's no more information available that I'm aware of.
 
I don't know although it has been discussed before. If 116372 or later then it should be high pressure regardless of the head feed position and have unscrolled spindles.



No, as there's no more information available that I'm aware of.
So, does the oil hole in the spindle, not matter which type, face away from center in all high pressure and towards center in all low pressure? Sorry, I stuck my nose where it does not belong and now just want to know so I don't confuse anyone else in the future!
 
So, does the oil hole in the spindle, not matter which type, face away from center in all high pressure and towards center in all low pressure?

High pressure the hole (with or without flat) should face out.

Low pressure shows the flat on the inside but not the position of the oil hole as it's not in the flat.
Atlas Rocker Spindles
 
I should have stayed out of it. I know almost nothing about pre-Commando. I was just trying explain why the feed was away from the hole in the rocker.

L.A.B provided much more info about the "flats". The flats I'm talking about have the oil hole in them and the spindles are not scrolled. I have no knowledge of the high/low pressure with the feeds on top of the head - the only high pressure I"m aware of is fed to the sides of the head.

In fact, I have an Atlas head like that looking for a home as I'll never have a use for it!
No problem. Thanks
 
Ok all I know what to do now! One last question. What is the purpose of the flat? Have anything to do with the delivery and velocity of the oil? Got to tell you this Forum has proven invaluable in aiding me with this build. Thanks everybody
 
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From what I have read, the flats are there to collect oil to improve lubrication to that area of the spindle.

Someone please correct if wrong.
 

Hope that will help ...
After reading this link, why is it that Dynodave says he would never put plain ( no flats) spindles in his engine? I guess I don’t fully understand. What exactly is a “scrolled” spindle?
 
So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up
 
So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up

IMO, the scroll and flats were to enhance oiling to the rocker bores and thence to the pushrods when the source of the oil was from the low pressure scavenge oil return. In the low pressure system, the oil pressure feeding the rockers is that necessary to lift oil from the bottom level of the oil tank to the upper level and thru a small hole restriction, a few psig at most.
In the high pressure system, oil is fed to the rockers at the same pressure as fed to the crank big ends, anywhere from 5 to 60 psig, depending on engine rpm and oil temperature. Obviously, way more pressure than that of the low pressure system.
Thus, the high pressure system is capable of delivering much more oil to the rocker boxes than the drainage system was ever designed for, and the oil supply enhancements of the scrolls and flats results in flooding of the rocker boxes.
The earliest solution to control over oiling the rockers was to reverse the flats. IMO, after Norton exhausted their inventory of scrolled and flatted spindles, it became obvious they could save machine costs by going to a plain spindle. Thus, your spindles are not likely to be problematic. To allay any fears, pull the rocker box covers after a run and visually check for oil. The least pooling of oil is sufficient.

Slick
 
I would use Commando style spindles that have flats for high pressure applications.
 
I would use Commando style spindles that have flats for high pressure applications.

A solution without cause for concern, as the final iteration in the evolution of the spindles should include all that Norton learned about this matter.
 
So here's my final thought now that I know which way they should face. Assuming the plain spindles that I have with no scrolling, and no flats, coming from a 1967 Atlas, was there a problem with these or should I be replacing them with non scrolled with flats type. It is a high pressure set up
It would not hurt a thing to use new plain spindles with the flats. Just face the flats away from the center of the head.

That is how the head in my '67 Norton 750 engine is set up and I do not have an over oiling issue. Spindles with flats are what came in '67 750 engine heads when they were built new if one is to believe the instructions in the Norton Villiers manual I have that was first published in March 1967.

I'm not sure why Dunstall used the plain spindles in the head unless that is all they had laying around the day they put it together.
 
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