Removing Bevel Drive Shaft Nut

[John Croucher]

Found the problem with the locked up drive line.  The bearing in the bevel shaft housing is frozen.  I broke it loose and will turn the opposite of the drive direction, but locks when rotating in the correct drive direction.

Now to remove the locking nut.  I used a chain saw sharpening stone to remove the indented portions on the nut.  But, the nut will not turn.  I am assuming it has right hand threads.  Clamped the splines in aluminum soft jaws in vice.  Used a 16 inch pipe wrench on nut.  Didn't move.  This nut should not be tight against the taper bearing beyond zero or slight. I am assuming it is corroded on since the bearing is corroded.

The odd part is the bearings turned freely when I installed the bevel box and had lubrication on it.  The bike came from Florida and had sand in odd places.  The drive shaft tube was clean when I removed it.  No signs of debris inside. 

[bigbikerrick]

Have you tried applying any heat to it? I like to use a small hand help butane torch to heat up the nut, all the way around, apply some kroil, or other penetrant such as 1/2 acetone 1/2 ATF, let it penetrate, then heat it again, and then try to remove it .
good luck
Rick.

[pehayes]

Are you writing about the input area of the bevel drive box itself?  Not in the shaft housing or u-joint area?
If you refer to the bevel drive box, there are TWO tapered rollers in there separated by a spacer and some adjustment shims.  The spec for that shaft nut is VERY high.  IIRC it is 129 to 144 foot pound.  That is a LOT.
You seem worried about excess pressure on the tapered roller bearing.  Doesn't happen.  The nut pressure is taken up by the inner races of the two bearings, the spacer, and the shims.  All acts like a compression sandwich.  No load on the bearing tapers. Nut is standard right hand thread.  Please clarify (maybe a pic) of exactly which nut you refer to.

Patrick  Hayes
Fremont CA

[John Croucher]

Are you writing about the input area of the bevel drive box itself?  Not in the shaft housing or u-joint area?
If you refer to the bevel drive box, there are TWO tapered rollers in there separated by a spacer and some adjustment shims.  The spec for that shaft nut is VERY high.  IIRC it is 129 to 144 foot pound.  That is a LOT.
You seem worried about excess pressure on the tapered roller bearing.  Doesn't happen.  The nut pressure is taken up by the inner races of the two bearings, the spacer, and the shims.  All acts like a compression sandwich.  No load on the bearing tapers. Nut is standard right hand thread.  Please clarify (maybe a pic) of exactly which nut you refer to.

Patrick  Hayes
Fremont CA

You clarified it perfectly.  Been a while since I worked on one of this part.  Forgot about the spacer and shim as the compression points.  Just glad the lock up occurred there and not further into the drive line. I will cut the nut off and replace with new. 

[Wayne Orwig]

Odd. Maybe the bearing cage came apart, or a roller exploded in there.

I have an old coupler that I welded a bead on each side of then clamp it in a vice. The weld keeps it from spinning.

Think about doing that and just putting in a new coupler, since they do wear out.

[Huzo]

Cutting the nut is the way I would go.
You may even find that once you are most of the way through, it will loosen enough to undo, due to expansion.
I have removed inners from half shaft tapered races in car differentials that way.

[n3303j]

You clarified it perfectly.  Been a while since I worked on one of this part.  Forgot about the spacer and shim as the compression points.  Just glad the lock up occurred there and not further into the drive line. I will cut the nut off and replace with new.

Not sure why you are set on cutting the nut. Went through this disassembly replacing the final drive preloaded taper roller input shaft bearings on my V11. You just have to apply some SERIOUS torque to remove the nut. If you are replacing the bearings you get to do it multiple times as you trial and error the preload. Fun way to spend a morning. Then you get to re-check the pinion to ring clearance and contact pattern. By the time I get it right the day is probably over.

[Huzo]

Maybe a rattle gun ?

[n3303j]

Seems this was part of the V11EV Project.
The other half was a spline coupler welded up to a socket so it could be fitted to a 200 ft/lb torque wrench.

A few motorcycle projects require heavy duty tools. There's a reason I own a 48 inch 3/4" drive breaker bar. (Older and weaker comes to mind)

[John Croucher]

Not sure why you are set on cutting the nut. Went through this disassembly replacing the final drive preloaded taper roller input shaft bearings on my V11. You just have to apply some SERIOUS torque to remove the nut. If you are replacing the bearings you get to do it multiple times as you trial and error the preload. Fun way to spend a morning. Then you get to re-check the pinion to ring clearance and contact pattern. By the time I get it right the day is probably over.

How did you hold the gear shaft from rotating?  While mine locked up, it did break loose in the direction of tightening, but turns when turning to loosen.  I clamped the splined end with soft Jaws in vice.  Twisted it out of vice.  Holding the gear end gives very little contact area when clamping.

I tried a rattle gun at two different friends locations.  Same problem, keeping the shaft from rotation While applying torque.

[n3303j]

I bought an extra spline coupler and welded it in a spare socket so I could put a torque wrench on it. The coupler could also be held in a significantly serious vise without worrying about damaging the male spline.

[jacksonracingcomau]

I bought an extra spline coupler and welded it in a spare socket so I could put a torque wrench on it. The coupler could also be held in a significantly serious vise without worrying about damaging the male spline.

Even easier and cheaper way
Grab one of your old worn uj’s ( every tonti owner must have worn a uj out by now )
Remove one yoke
Use bar through yoke, I’ve been using the same yoke for 40 odd years, I’ve rebuilt many many gearboxes and final drives with this yoke
For fine spline version use a worn out convert uj (maybe harder to find these days)

[John Croucher]

Even easier and cheaper way
Grab one of your old worn uj’s ( every tonti owner must have worn a uj out by now )
Remove one yoke
Use bar through yoke, I’ve been using the same yoke for 40 odd years, I’ve rebuilt many many gearboxes and final drives with this yoke
For fine spline version use a worn out convert uj (maybe harder to find these days)

Probably have one of these two parts in a tote with salvage parts.

[Tom H]

As Wayne mentioned, an old coupler would work, or as mentioned an old U joint to hold the shaft.

Tom

[John Croucher]

No lube.  There are signs the bearing had run dry for a while.  The bearing block has 2 holes for gear oil to flow through. One was blocked with a burr from the milling of the flats on opposite sides.

The new bearing from NAPA were from two mfg. SKF AND FAG.  Same physical dimensions on i.d, o.d. and width.  Taper was different.  Shimmed up good. 

[n3303j]

What is that crud piled up on the roller?
Hope it's not moly additive.

[John Croucher]

What is that crud piled up on the roller?
Hope it's not moly additive.

Bearing cage

[Alfetta]

The new bearing from NAPA were from two mfg. SKF AND FAG.  Same physical dimensions on i.d, o.d. and width.  Taper was different.  Shimmed up good.

I have not studied a MG gearbox, and i'm sure your new bearing will fit and work. however I would take a few dimensions to know the potential effect of the differing taper angle. the point where the angle intersects the axis of rotation (of both bearings) is the moment arm that hold the shaft. If the new taper increases this distance, your box is most likely stronger the the original, however the inverse is also a potential.