10EE Rear Bearing Diagrams, Changes

[Cal Haines]

This post is copied from Need help with my new 10EE - post #223. It makes more sense to discuss this in its own topic.​

I'll discuss detail of the 10EE's rear bear section, including the labyrinth oil and how things have changed over time.

This is a section of drawing EE-99 (October 1941), showing the rear spindle bearing and LH clutch gear:

(This is a drawing that I color-coded several years back and have posted before.) The drawing appears to be from the redesign of the Sundstrand-drive 10EE to create the inline-exciter era 10EE.

The Rear Spindle Bearing Spacer [Parts Picture E2A-7] is Monarch part EE-1125, shown in dark blue, above. (This same part has been in use from the Sundstrand 10EEs all the way to 1980 and probably beyond.) It's job is to help control the position of the rear spindle bearing on the spindle. Note that it rotates with the spindle; if it's a loose fit, it will cause balance and vibration issues. The clearance between the spacer and the spindle, show on the drawing above, is 0.0002 to 0.0009", so it should be a fairly close clearance fit.

Both ends of a 10EE's spindle employ a form of labyrinth seal to prevent oil from escaping. The rear seal on early round-dial machines consists of three parts:

• Rear Bearing Oil Throw Plate [E2A-5; EE-1116] (aka oil slinger), shown in orange, above.
• Rear Spindle Bearing Oil Deflector Retainer [E2A-3; EE-1031], shown in medium blue, above.
• Rear Spindle Bearing Oil Deflector [E2A-4; EE-1122], shown in purple, above.

Machines with the T-handle gearbox tend to have this configuration labyrinth seal; lever handle gearbox machines us a 2-piece seal, which I'll discuss later.

The rear retainer, EE-1031, attaches to the headstock casting via 4 cap screws. Note that it does not contact the outer race of the rear spindle bearing. It has a counterbore, facing away from the headstock, to accept the oil deflector, EE-1122. The oil deflector has an L-shaped cross-section an is pressed into the counterbore in the retainer. Together, the deflector and the rear retainer form a U-shaped, annular cavity that encloses the fin on the throw plate. Not shown on the drawing is the drain hole at the bottom of the retainer and the channel that routes oil that collects in the annular cavity into the headstock's main (center) reservoir. Both the deflector and the retainer are stationary and do not contact the spindle. This design apparently did not incorporate a gasket between the retainer and the headstock.

The throw plate, EE-1116, is a tight fit to the spindle, rotates with the spindle and does not contact the deflector or retainer. It's held in position by the rear bearing on one side and the Spindle Lock Gear, [E2A-95; part EE-2302] on the other. The lock gear is, in turn, held in place by the Spindle Sheave or drive pulley (not shown on the diagram), which is also a close fit to the spindle (0.0005" clearance, max).

The way the seal works is that any oil that makes its way between the spindle and the rear retainer enters the annular cavity or moves to the throw plate. As the spindle rotates, oil on the throw plate is spun outward into the annular cavity, where it can make its way to the drain at the bottom.

 

[Cal Haines]

This is a section of square-dial 10EE headstock drawing EE-4-35, dated 1-29-1944:

I color-coded it using the same colors as the 1941 drawing in the previous post. This drawing dates to about the time that the square-dial 10EE was in initial production and is for a headstock with three oil sight-glasses.

The rear seal has been changed to a two-piece seal, consisting of:

• Rear Bearing Oil Throw Plate [EE-2614], shown in orange, above.
• Rear Spindle Bearing Oil Deflector Retainer [EE-2614], shown in medium blue, above.

The throw plate's "fin" has been moved inside the retainer, so that most of the oil will get thrown off in the rear bearing cavity. Any oil that migrates past the fin and the ID of the retainer will find its way to an angled notch on the throw plate and get spun off into a annular channel in the deflector. The channel has a semicircular cross section with a drain system at the bottom that routes any oil that makes its way there into the headstock's center reservoir. A gasket, EE-2405, is shown between the retainer and the headstock casting.

The EE-24xx part numbers date to early 1942 when the round-dial gearbox was redesigned to replace the T-handle cone-gear clutch with the lever found on later round-dials. While the above drawing is for a square-dial headstock, round-dial's with lever gearboxes also tend to have this configuration of labyrinth seal.

The Left Hand Clutch Gear [E2A-10, EE-2110 (light blue, above)] is retained from the 1941 design, but the bushing (EE-2288, yellow, above) has been changed. In fact, between 1941 and debut of square-dial 10EEs, the bushing underwent a number of changes. Here's my summary from another thread:

I ... concluded that the ... bushings were a problem and that the design was changed several times during the round-dial period: The bushing used in the original design--the Sundstrand hydraulic machines--was redesigned in 1941 when the inline exciter was rolled out. (Perhaps that's when the countersunk oil hole was added?) Sometime prior to mid 1942 (very likely at the time of the major redesign that resulted in the piggyback exciter round-dial) the bushing was changed again, adding three oil holes on the nose and an annular oil channel, fed by oil holes in the headstock. In late 1943 the headstock casting was changed to add the reservoirs over the bushings. Perhaps at that time they experimented with a different bushing material (my machine appears to have bronze bushings). At some point after that, oil channels were again machined into the headstock casting, in the reservoirs over the bushings, and the 1942 bushing was in use. With the square-dial redesign, the bushing material was changed (bronze?) and oil lines were added (fed by the wiper on the tach gear) to lubricate the bushings. That apparently fixed the problem.​

The rear spindle bearing itself is a double-row bearing. It's unknown at this writing if it's the same New Departure 5210 bearing shown on drawing EE-99. At least as late as 1944, round-dials continued to use the ND 5210 bearing (link).

 

[Cal Haines]

This is a section of headstock drawing 202.268, revision H, dated 9-30-1985:

The color codes from the previous two drawings were used. This drawing is for a headstock with one oil sight glass.

The labyrinth rear seal has been changed by incorporating the throw plate into the spindle lock gear, part 25869. (Apparently the fin on the throw plate was not necessary.) Note that the gear/throw-plate has the same angled notch used in the earlier throw plate design (EE-2614). The retainer, part 25868, has the same annular cavity to collect oil as used in the earlier retainer (EE-2615). The retainer has been made deeper to accommodate two single row bearings in place of the double-row bearings used in the previous designs, but is otherwise largely the same. The same retainer gasket from the 1944 design, EE-2405, is used in this design. The Left Hand Clutch Gear assembly is essentially the same as that used in the 1944 design.

 

[GrantGunderson]

This is a section of headstock drawing EE-4-35, dated 1-29-1944:
View attachment 375421
I color-coded it using the same colors as the 1941 drawing in the previous post. This drawing dates to about the time that the square-dial 10EE was in initial production and is for a headstock with three oil sight-glasses.

The rear seal has been changed to a two-piece seal, consisting of:

• Rear Bearing Oil Throw Plate [EE-2614], shown in orange, above.
• Rear Spindle Bearing Oil Deflector Retainer [EE-2614], shown in medium blue, above.

The rear spindle bearing itself is a double-row bearing. It's unknown at this writing if it's the same New Departure 5210 bearing shown on drawing EE-99. At least as late as 1944, round-dials continued to use the ND 5210 bearing (link).

Cal, My machine is July 44, and this drawing matches the rear seal of it. My head stock has 3 oil sight gauges, but it has the ND5210 rear bearing. Out of curiosity, do we know what the new bearings are?

 

[Cal Haines]

I wasn't clear in my post, but that's a square-dial headstock drawing. (I've gone back and edited to include that fact.) And yes, the rear bearing labyrinth seal on your machine is like that shown in the drawing, but I believe that change predates the 1944 square-dial headstock design shown. Based on the part numbers, the two-piece labyrinth seal design is from 1942. I'm sure there are other headstock drawings out there, but these are the only three versions that I've seen.

I'm pretty sure that the bearing numbers for the square-dial double-row rear bearing have been posted before, but I don't have them at hand.

 

[GrantGunderson]

Also, out of curiosity, what is the difference between the regular round dial headstock and the 3 sight glass ones? I dont think I released there was even a difference in the number of sight glasses.

 

[Cal Haines]

Sometime in the mid 1960s the square-dial headstock was redesigned to eliminate the separate oil reserovirs for the front and rear bearings. The lubrication spec for the 3-sight glass (3-reservoir) headstocks called for DTE Heavy-Medium for the center reservoir and DTE Light for the bearing reservoirs. The single-sight-glass headstocks use DTE Light for everything.

I don't recall seeing a photo of the inside of a single-sight-glass headstock, but apparently the tach gear lifts oil to a reservoir over the tachometer shaft and four oil lines carry it from there to the clutch gear bushings and spindle bearings.

According to this post by rimcanyon, ND 5210 bearings were used into the early 1960s:

Source for ND 5210 Rear Spindle Bearings for 10EE's through early 60's

ND 5210's are getting harder to find, but there is still an availability of the 5210 with shields. the shields can be popped off and you have a normal 5210. They are called 55510's. The bearings say 5210 on the side...

www.practicalmachinist.com

 

[Hobby Racer]

I'm glad this thread got post. Now I know for sure that I put my oil Rear Oil Bearing Throw Plate in backwards!

I'll have to get at fixing that.

 

[grounding]

This post is copied from Need help with my new 10EE - post #223. It makes more sense to discuss this in its own topic.​

I'll discuss detail of the 10EE's rear bear section, including the labyrinth oil and how things have changed over time.

This is a section of drawing EE-99 (October 1941), showing the rear spindle bearing and LH clutch gear:
View attachment 375420
(This is a drawing that I color-coded several years back and have posted before.) The drawing appears to be from the redesign of the Sundstrand-drive 10EE to create the inline-exciter era 10EE.

The Rear Spindle Bearing Spacer [Parts Picture E2A-7] is Monarch part EE-1125, shown in dark blue, above. (This same part has been in use from the Sundstrand 10EEs all the way to 1980 and probably beyond.) It's job is to help control the position of the rear spindle bearing on the spindle. Note that it rotates with the spindle; if it's a loose fit, it will cause balance and vibration issues. The clearance between the spacer and the spindle, show on the drawing above, is 0.0002 to 0.0009", so it should be a fairly close clearance fit.

Both ends of a 10EE's spindle employ a form of labyrinth seal to prevent oil from escaping. The rear seal on early round-dial machines consists of three parts:

• Rear Bearing Oil Throw Plate [E2A-5; EE-1116] (aka oil slinger), shown in orange, above.
• Rear Spindle Bearing Oil Deflector Retainer [E2A-3; EE-1031], shown in medium blue, above.
• Rear Spindle Bearing Oil Deflector [E2A-4; EE-1122], shown in purple, above.

Machines with the T-handle gearbox tend to have this configuration labyrinth seal; lever handle gearbox machines us a 2-piece seal, which I'll discuss later.

The rear retainer, EE-1031, attaches to the headstock casting via 4 cap screws. Note that it does not contact the outer race of the rear spindle bearing. It has a counterbore, facing away from the headstock, to accept the oil deflector, EE-1122. The oil deflector has an L-shaped cross-section an is pressed into the counterbore in the retainer. Together, the deflector and the rear retainer form a U-shaped, annular cavity that encloses the fin on the throw plate. Not shown on the drawing is the drain hole at the bottom of the retainer and the channel that routes oil that collects in the annular cavity into the headstock's main (center) reservoir. Both the deflector and the retainer are stationary and do not contact the spindle. This design apparently did not incorporate a gasket between the retainer and the headstock.

The throw plate, EE-1116, is a tight fit to the spindle, rotates with the spindle and does not contact the deflector or retainer. It's held in position by the rear bearing on one side and the Spindle Lock Gear, [E2A-95; part EE-2302] on the other. The lock gear is, in turn, held in place by the Spindle Sheave or drive pulley (not shown on the diagram), which is also a close fit to the spindle (0.0005" clearance, max).

The way the seal works is that any oil that makes its way between the spindle and the rear retainer enters the annular cavity or moves to the throw plate. As the spindle rotates, oil on the throw plate is spun outward into the annular cavity, where it can make its way to the drain at the bottom.

Cal, mine does not have the hole at the bottom of the retainer. The retainer seems to have a very thin gasket material on the outer ring of it. Didn't get a chance to dig into that last night. May have been someone did after the factory??

 

[Cal Haines]

Cal, mine does not have the hole at the bottom of the retainer. The retainer seems to have a very thin gasket material on the outer ring of it. Didn't get a chance to dig into that last night. May have been someone did after the factory??

The gasket may have been added after the fact.

Your headstock has the oil return hole, so it doesn't make sense that the retainer doesn't. This might explain why you have the oil leak.

Here's one of your photos of the headstock side of the retainer:

Look at the area circled in red.

Here's an enlarged section of the photo:

Something is going on right about where the drain hole should be. It almost looks like someone soldered it shut. Have a close look at that spot and on the other side of the retainer at that location and see what's up.

It may also be the case that the gasket is what's blocking the drain.

 

[Cal Haines]

Whatever the defect is, it can't be the oil return hole. The return hole would be on the part of the flange with the bolt holes, under the gasket. Look carefully at the other side, midway between each pair of bolt holes and see if you can find a radial hole that would lead to a horizontal hole and line up with the drain hole in the headstock.

 

[grounding]

I think that’s a flaw in the part. I don’t see the return hole anywhere?

 

[Cal Haines]

Huh? OK, no oil return passage then. I saw Hobby Racer's post on your thread and thought that was your headstock, my mistake.

I don't understand what the idea was, having a labyrinth seal with no provision to drain off the oil that accumulates there. The front bearing's labyrinth seal (at least on most machines) has a small drain hole at 6 O'clock, on the outside of the retainer, to drain off any oil that accumulates there. Does yours?

I would probably add a drain hole to the oil deflector, similar to the front bearing's. Or you might want to add an oil return passage, like the newer machines have.

 

[GrantGunderson]

The oil return line in mine is right next to one of the screw holes. So you i if that gasket gets removed you will find it.



Pipe cleaner shows oil passage.

 

[Cal Haines]

Terry's retainer bolt holes are different than yours by 45 degrees. And he has no return oil passage in his headstock.

 

[GrantGunderson]

Terry's retainer bolt holes are different than yours by 45 degrees. And he has no return oil passage in his headstock.

Interesting.

 

[grounding]

Terry's retainer bolt holes are different than yours by 45 degrees. And he has no return oil passage in his headstock.

Funny that I have the return hole at the front, but not the back?