More EE spindle questions

Working at fitting up the spindle (new bearings) on my 63' Modular drive. The head stock is the earlier style having three sight glasses.
I have no operating history with this machine so there are some questions

I am under the impression that these 3 glass head stocks can have issues with the oil draining out of the spindle bearing cavities.

I see that Monarch changed the slinger style when they went to the single sight glass head stock.
Of the changes, one includes an o-ring to seal the OD of the forward spindle slinger....Plus a different design on the slinger internal geometry itself.

Thinking that going with the later design might help reduce the oil migration from the spindle bearing cavities.

I have an original "late" spindle side slinger (thanks Dave) and i have reverse engineered the matching outside ring ...I realize that there are some differences with the oil drillings.
Looks like it would be possible to add the drain back and retaining screw drilling/tapping.....

Anyone here have any thoughts about doing this....Am i swinging at windmills, or is there any value in going this route....
Cheers Ross

I expect you know this already, but round dial machines use the exact same oil slinger setup as 3-sight glass square dial machines. So there are many thousands of 10EE's with the older system. I know that some of them leak oil from the front oil reservoir. But I think it is a small percentage. Maybe it is due to removing and reinstalling the outer oil slinger, but I am not sure. Scott@Monarch has said he does not know why some leak and some don't. I have a theory that the leak occurs via the oil drain that runs from the front of the headstock to the center oil reservoir. i.e. the only thing stopping it from happening is the gasket between the spindle flange and the headstock, so a bit of crud, a torn or folded gasket, a warped flange might be the cause. I also am of the opinion that the inner oil slinger itself has nothing to do with the leak; i.e. the leak happens when the machine is sitting unused, so either the oil is getting under the outer part of the slinger that is pressed into the headstock, or the oil is getting out via the oil drain. Putting an o-ring into the outer part of the slinger sounds like a good preventive step, but you might not need it.

Dave:
Thanks for taking the time to share your thoughts on this.....
Some stuff here to consider.
I do have the original single step slinger and i have already modified it to carry an "O"-ring on the OD, perhaps that is good enough...Have to think about all this.

Not sure i really understand the operating principle of the oil system. Seems that the oil drain back to the center sump should not cause any lowering of the oil in the forward oil cavity.
Its intended to drain, and even if it leaked its still a drain.....

Now if the front spindle cover was leaking at a point below the height of the normal drain, then i could see that as an issue....Guess i need some time looking at all this.
Cheers Ross

Thinking about this more.
I think its more likely that the fit of the front bearing in the headstock is a factor here....
If the bearing fit was such that oil could leak past the front bearing OD it would cause the oil level to drop in the front housing. Its like making the drain hole lower.
A housing that was slightly out of round or had small scratches in its surface might allow oil to leak past the bearing. In a perfect setup the bearing should be oil tight.
In real operation the bearing gets warm and expands more than the housing and keeps it oil tight...On cool down sitting idle the bearing will shrink and could again allow oil to escape....

Cheers Ross

AlfaGTA said:

Not sure i really understand the operating principle of the oil system. Seems that the oil drain back to the center sump should not cause any lowering of the oil in the forward oil cavity.
Its intended to drain, and even if it leaked its still a drain.....

Click to expand...

The overflow in the front is actually the front oil slinger drain. I.e. if the gasket is a good fit, the path the oil has to take is quite a bit higher than the top of the gasket, almost as high as the spindle. I think it is for oil that wicks from the bearings to the spindle then gets thrown off on the inside of the front flange. From there it passes down a hole in the front flange and through a hole in the bottom of the gasket back to the center oil compartment.