Main Shaft Dragging in Sleeve Gear?

Dan1950

Dan1950

1974 MK II Roadster
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I'm assembling my gearbox with a new sleeve gear and main shaft bearings. There is no runout on either end of the main shaft nor is there any runout on the sleeve gear. The main shaft slips into the sleeve gear and rotates feely but as the inner case is slid over the studs in the case the main shaft starts to bind. However, it does not get any worse as the nuts are snugged down.

I can hold the main shaft with slip joint pliers and rotate the sleeve gear by hand but it does have a bit of drag.

Is this an indication of a serious problem?

In the morning I think I will put my dial indicator on the end face of the sleeve gear to see if it might be misaligned.
 
Dan1950 said:
I'm assembling my gearbox with a new sleeve gear and main shaft bearings. There is no runout on either end of the main shaft nor is there any runout on the sleeve gear. The main shaft slips into the sleeve gear and rotates feely but as the inner case is slid over the studs in the case the main shaft starts to bind. However, it does not get any worse as the nuts are snugged down.

I can hold the main shaft with slip joint pliers and rotate the sleeve gear by hand but it does have a bit of drag.

Is this an indication of a serious problem?

In the morning I think I will put my dial indicator on the end face of the sleeve gear to see if it might be misaligned.
Click to expand...
Did you check the mainshaft bearing in the inner cover? If you replaced it, are you sure it's properly home. Have you tightened the timing side mainshaft nut? Are you sure that the drive side main bearing is all the way home? Have you tightened the sprocket nut? Mostly long-shots but worth checking.

BTW, you should be able to hold the mainshaft with a finger and thumb and turn the sleeve gear and vice versa.
 
The shaft is set axially by the nut on its left hand side and all should spin nicely, the sleeve gear oil seal will add some drag but not to the inner shaft.
If it is not pulled up at the bearing it could cause a problem at the shoulder and inner side of the sleeve gear.

I use a machined sleeve that fits over the sleeve gear outer end so that when the sleeve gear is installed in the bearing, that sleeve seats on the bearing inner race so there is no pressure on the bearing itself.

The gearbox should spin freely in all gears and select all gears on the bench easily.

Main Shaft Dragging in Sleeve Gear?
 
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Have you replaced the sleeve gear BEARING?

Main Shaft Dragging in Sleeve Gear?
 
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concours said:
Have you replaced the sleeve gear BEARING?

View attachment 84531
Click to expand...
Yes. I had the sleeve gear pressed into the bearing with a 1/1/4" x 2" pipe nipple supporting the inner race. I suspect that the mainshaft bearing on the other end may not be seated properly. I will check that out later today.
 
Dan1950 said:
Yes. I had the sleeve gear pressed into the bearing with a 1/1/4" x 2" pipe nipple supporting the inner race. I suspect that the mainshaft bearing on the other end may not be seated properly. I will check that out later today.
Click to expand...
If you look very close at my image, you'll see I had a bearing with insufficient radius, and could not work.
 
concours said:
If you look very close at my image, you'll see I had a bearing with insufficient radius, and could not work.
Click to expand...
Both the sleeve gear and bearing were purchased from Andover Norton.

There doesn't seem to be a problem with the sleeve gear itself. The mainshaft will rotate quite freely in the sleeve gear until the inner cover is installed, then there is a slight binding.

I checked that the inner cover bearing was seated completely using the anvil flat on my large Wilton vise as a backup. It seemed that the bearing might not have been seated completely. There is still some drag but I can hold the mainshaft with my fingers and rotate the sleeve gear now.

The original sleeve gear had more clearance in the bushings than the new one. I wonder if, for some reason, there is some misalignment built into the gearbox case and inner cover?

Also, there is end play in the mainshaft before the nut is tightened at the inner case bearing so there is no interference in that respect..
 
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Dan1950 said:
I'm assembling my gearbox with a new sleeve gear and main shaft bearings. There is no runout on either end of the main shaft nor is there any runout on the sleeve gear. The main shaft slips into the sleeve gear and rotates feely but as the inner case is slid over the studs in the case the main shaft starts to bind. However, it does not get any worse as the nuts are snugged down.

I can hold the main shaft with slip joint pliers and rotate the sleeve gear by hand but it does have a bit of drag.

Is this an indication of a serious problem?

In the morning I think I will put my dial indicator on the end face of the sleeve gear to see if it might be misaligned.
Click to expand...
I recently purchased an AN sleeve gear. There were fitment problems - in my case the nut wouldn't thread on without a massive amount of force. I bring this up as I am suspecting there "may" be a quality issue with a batch of sleeve gears.
 
The shaft ball bearing on the right hand side if not seated slightly (and shaft pulled up to it with the outer nut) would simply increase the shaft shoulder to sleeve gear inner side bush clearance.
That would decrease any chance of drag.
 
brucecostello said:
I recently purchased an AN sleeve gear. There were fitment problems - in my case the nut wouldn't thread on without a massive amount of force. I bring this up as I am suspecting there "may" be a quality issue with a batch of sleeve gears.
Click to expand...
I just had to check that out. The nut screws on freely.
 
Time Warp said:
The shaft ball bearing on the right hand side if not seated slightly (and shaft pulled up to it with the outer nut) would simply increase the shaft shoulder to sleeve gear inner side bush clearance.
That would decrease any chance of drag.
Click to expand...
It's not a problem with axial clearance.

Without the inner cover bearing nut on the end of the mainshaft there is plenty of end thrust clearance.

The problem is that the bearing bores are not in alignment. Perhaps at some time over the last 47+ years, a mismatched inner cover was fit to the original GB case. The misalignment is not severe, just enough to add some drag between the sleeve gear and mainshaft.

I have checked the seating of the sleeve gear bearing and inner cover bearing and they are both seated fully and square. As far as I can tell, a misalignment of about .005-.007 would cause the binding with the clearance that is present with the new sleeve gear bushings. I am going to try honing the bushing slightly to provide another .001 or so clearance and see what that yields.
 
I want to thank everyone for their input. Sometimes when I "think out load" in my posts it seems like I am being argumentative. That is not the case. I absorb what is being offered and compare it to what I am able to deduce with my 1st hand experience.

I have come to these conclusions.

A) either the sleeve gear of inner cover gear bearings are not seated square in their bores. Something that does not appear to be the case as near as I can tell although all I have are my non-calibrated verifications.

B) The bores in the main GB case and inner cover are misaligned slightly. Again this is not something I can tell with certainty. The drag does not become excessive when the inner cover is slid over the studs, but becomes obvious as the dowel pin in the GB case pin engage the inner cover.

There is little or no runout in any of the components that might affect this.

My options as I see them are to get new bearings and re-do everything I have accomplished thus far with no guarantee that there will be a different outcome .

Hone the bushings in the sleeve gear to reduce the drag in the sleeve gear.
 
Dan1950 said:
Both the sleeve gear and bearing were purchased from Andover Norton.

There doesn't seem to be a problem with the sleeve gear itself. The mainshaft will rotate quite freely in the sleeve gear until the inner cover is installed, then there is a slight binding.

I checked that the inner cover bearing was seated completely using the anvil flat on my large Wilton vise as a backup. It seemed that the bearing might not have been seated completely. There is still some drag but I can hold the mainshaft with my fingers and rotate the sleeve gear now.

The original sleeve gear had more clearance in the bushings than the new one. I wonder if, for some reason, there is some misalignment built into the gearbox case and inner cover?

Also, there is end play in the mainshaft before the nut is tightened at the inner case bearing so there is no interference in that respect..
Click to expand...
Did you check to see if the main shaft isn't slightly bent?
 
Dan1950 said:
Yes. I had the sleeve gear pressed into the bearing with a 1/1/4" x 2" pipe nipple supporting the inner race. I suspect that the mainshaft bearing on the other end may not be seated properly. I will check that out later today.
Click to expand...
The sleeve gear should not need to be pressed into the bearing. They are a snug slip fit.
 
Dan1950 said:
I want to thank everyone for their input. Sometimes when I "think out load" in my posts it seems like I am being argumentative. That is not the case. I absorb what is being offered and compare it to what I am able to deduce with my 1st hand experience.

I have come to these conclusions.

A) either the sleeve gear of inner cover gear bearings are not seated square in their bores. Something that does not appear to be the case as near as I can tell although all I have are my non-calibrated verifications.

B) The bores in the main GB case and inner cover are misaligned slightly. Again this is not something I can tell with certainty. The drag does not become excessive when the inner cover is slid over the studs, but becomes obvious as the dowel pin in the GB case pin engage the inner cover.

There is little or no runout in any of the components that might affect this.

My options as I see them are to get new bearings and re-do everything I have accomplished thus far with no guarantee that there will be a different outcome .

Hone the bushings in the sleeve gear to reduce the drag in the sleeve gear.
Click to expand...
Try this: Remove the bearing in the inner cover and put it together. Then measure the gaps up, down right, and left while holding towards those directions with a finger.

Also, assembled this way, rotate the mainshaft trying to put no side pressure on it and watch the other end. I had the same symptoms when I had a main shaft slightly bent in the middle. The bend was slight enough that it took me a while to convince myself that it was bent but I thought I could see it moving around in the hole where the bearing should be. To finally prove it, I put the sleeve gear in my vice (lightly), put the mainshaft through it and used a dial indicator to check the runout - .005" if I remember right.
 
A11BFDE2-958C-4E20-A398-CD319A84A19C.jpeg

Some Andover Norton transmission parts quality escapes (2015)

I had the opportunity to repair my failed transmission (still working, but 2nd had a funny "thump, thump, thump" noise. Disassembly revealed a LOT of damage.... I set to work inspecting (the case, sleeve gear and first gear lay were the only usable moving parts) and ordering parts. When I...
www.accessnorton.com www.accessnorton.com
 
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N0rt0nelectr@ said:
Did you check to see if the main shaft isn't slightly bent?
Click to expand...
I made some "V" blocks and checked the mainshaft .000" runout at all points.
marshg246 said:
The sleeve gear should not need to be pressed into the bearing. They are a snug slip fit.
Click to expand...
That may be the problem, it was .002" interference fit.

I think I will get some new bearings and start over.
 
If the sleeve gear pushed in by hand that would be a concern to me, its not a Japanese motorcycle if the interference fit was to high that would be noticeable at hand rotation.
I simply press them in over a machined tube being easy to do so (over hammers etc) and independent from both the gearbox case and bearing outer race.

If the dowel pins seem to cause a problem remove them to check taking for granted the mating faces are free from any form of riser and see if the problem does disappear.
That or Acetone the shaft and bushes so the shaft running area can be 'Texta ed to see if it gets rubbed off more so at one (or two) spots at rotation perhaps.

I installed new AN sleeve gear bushes with a machined step mandrel, it was not a fit and install job.
In saying that I did three gearboxes at once and all operated and spun nicely (Any drag was the output seal only installed last)
 
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Time Warp said:
if the interference fit was to high that would be noticeable at hand rotation.
Click to expand...
As a mater of fact the sleeve gear bearing had a slight amount of drag once the gear was pressed home. It was smooth though so I was not concerned. There was a small step on the surface that went into the bearing. The spline end and the 1st 1/4" or so of the smooth surface was a snug hand press fit. The step measured .002" larger.

I think my problem lies in the sleeve gear alignment. With that tight of a fit within the ball bearing races, any misalignment of the bearing itself would be crucial.

I will also remove the dowel pins for ma trial fit as you suggest.
 
Time Warp said:
If the sleeve gear pushed in by hand that would be a concern to me, its not a Japanese motorcycle if the interference fit was to high that would be noticeable at hand rotation.
I simply press them in over a machined tube being easy to do so (over hammers etc) and independent from both the gearbox case and bearing outer race.
Click to expand...
Workshop manual 065146

Section D5, Step 10: "Remove the sleeve gear by tapping gently through the bearing into the gearbox"

Section D9, Step 8: "Fit the countershaft (sleeve gear) through the bearing and seal. Fit sprocket spacer in place inside seal"

I've done quite a few - never had to press a sleeve gear into a bearing and would not if the need arose - too much chance of damaging the case pressing it in and later pressing it out. Of course, they are not supposed to be loose in the bearing. Generally, you start it into the bearing wiggling and once in a little it will slide in with no wiggle at all. Sometimes they will get part way in a get stuck - usually means a bit of grit, lint, or maybe dust - pull it out, clean and try again.

In truth, even if it was an easy slip fit in the bearing it wouldn't matter as the bearing, spacer and sprocket are sandwiched together and tightened.
 
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