Sleeve Gear Bearing Failure

Got some time to clean up the gear cluster and a 1st crack at the casing. Lots of metal bits...

Looks like 4th layshaft is on the shaft correctly. The teeth will have to be cleaned up. How does this come off the shaft? Ist and 2nd pulled off.



What is left of the Sleeve Gear Oil Seal revealed itself...



What else should I be looking at replacing while the gear box is open. Here is some wear on 1st mainshaft. Hard to get the lighting right...

you will probably need to use a brg puller to get the inner race of the end of the layshaft.

the sleeve brg running in grease?

Niagara850 said:

Looks like 4th layshaft is on the shaft correctly.

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Yes, although the gap between the inner race and the gear looks as if the race wasn't pressed fully home.

850commando said:

the sleeve brg running in grease?

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I noticed what looked like grease! Was it a sealed or shielded bearing?

Use the bearing puller on the layshaft 4th gear, much easier to get behind it than the bearing inner, both will come off.

L.A.B. said:

I noticed what looked like grease! Was it a sealed or shielded bearing?

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Bearing sealed on both sides might explain the failure.

Triton Thrasher said:

Bearing sealed on both sides might explain the failure.

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Oh Dear!

Could be the remains of a rubber seal in the first image?
(Click image twice to enlarge)


(The centre stand pivot also looks as if it is in need of some attention!)

Yes, although the gap between the inner race and the gear looks as if the race wasn't pressed fully home.

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Definitely axial play between the inner race, 4th lay, 3rd lay and the stop in the layshaft. maybe 1/32? Are these supposed to be tight with no play between the three? If so this may be the root cause of the failure

I noticed what looked like grease! Was it a sealed or shielded bearing?

Click to expand...

That's not grease, it's a hard plasticy type material, there is some on the lip of the case also. I assume it's item #9 Gear Sleeve Oil Seal in the parts diagram. It was on the outside / case side of the bearing. Don't believe the bearing was sealed from the pieces found in the case. There were plastic bits from the bearing cage and metal shavings of different sizes. I found pics from March 2012 when I installed the layshaft roller. I did it insitu and didn't pull the mainshaft, primary et al and can't see the bearing behind the sleeve gear.

L.A.B. said:

Could be the remains of a rubber seal in the first image?
(Click image twice to enlarge)

(The centre stand pivot also looks as if it is in need of some attention!)

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Yes the pivot is loose and needs to be tightened.

Niagara850 said:

Definitely axial play between the inner race, 4th lay, 3rd lay and the stop in the layshaft. maybe 1/32? Are these supposed to be tight with no play between the three? If so this may be the root cause of the failure

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It should go up against the raised section of 4th gear/splined shoulder of the layshaft without (free) 3rd gear binding although it's hard to say if that clearance caused the failure or not but would likely have reduced the shaft end float.

Niagara850 said:

Don't believe the bearing was sealed from the pieces found in the case.

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OK, as there seemed to be what looked like the remains of a rubber seal but maybe not.




If it was the bearing outer race that moved against the gear when it failed causing the gear rub mark then I would have thought the race would've turned yet the rub mark shows no evidence of that so perhaps the bearing wasn't fitted all the way into the housing?

Niagara850 said:

Definitely axial play between the inner race, 4th lay, 3rd lay and the stop in the layshaft. maybe 1/32? Are these supposed to be tight with no play between the three? If so this may be the root cause of the failure

Click to expand...

1/32 sounds excessive, there has to be some clearance or 3rd would be locked to the shaft by 4th pressing on it. However even 1/32 has no effect on the 4th rubbing on the main bearing outer as long as its installed the correct way round as the roller bearing inner stops it going too far over. So not good but also not root cause.

I took the gear clusters, inner cover and bearing remains over to a friend in the CVMG for inspection. He's owned a number Nortons and is down to a Dominator and an Atlas among BSA's and Triumph's. Well equipped garage I might add. British trained metal worker who worked in the aircraft industry. Great at pounding out alloy tanks but I digress..

He wasn't concerned about the play between inner race and gears on the layshaft. When I replaced the layshaft bearing I shimmed the runout to 8 thou if memory serves me correctly. We knocked the remains inner race off the Sleeve Gear, and the remains of the Oil Seal out of the inner race. All parts accounted for. He thinks the Sleeve Gear bearing was spinning with the shaft. He had a new bearing which slipped into place too easily on to the shaft and he recommend using Locktite between bearing and shaft. You could see it got pretty hot. The Mainshaft Bearing was noisy so it will be replaced. Gear teeth are all good,with exception of honing a slight burr off 4th lay. Bushings appear to be in good shape with no undo play. Still have to flush and clean the Outer Cover and order a few parts (Spacer, Seal and Mainshaft Bearing). Got off pretty lucky.

Does any know the number /spec for the two bearings. I may be able to get the mainshaft bearing at Canadian Bearing. The Gear sleeve bearing I have is marked SKF RLS 9 1 1/4 UTLD. Just want to make sure it is correct . Outer race matches and it fits on the shaft.

Forensics



The thread should be renamed Gear Sleeve Bearing Failure if I can figure out how...

Niagara850 said:

The Gear sleeve bearing I have is marked SKF RLS 9 1 1/4 UTLD. Just want to make sure it is correct .

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Yes, RLS 9, 1 1/4 (but perhaps buy a steel caged bearing instead of plastic?) and mainshaft timing side is RLS 5.

Niagara850 said:

The thread should be renamed Gear Sleeve Bearing Failure if I can figure out how...

Click to expand...

I can do that. Gear Sleeve...or Sleeve Gear Bearing Failure?

L.A.B. said:

Yes, RLS 9, 1 1/4 (but perhaps buy a steel caged bearing instead of plastic?) and mainshaft timing side is RLS 5.




I can do that. Gear Sleeve...or Sleeve Gear Bearing Failure?

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Thanks for the Bearing info! The bearing my friend gave me has a steel cage and yes 'Sleeve Gear Bearing Failure' Dyslexia setting in?

Be careful, that your bearing fits properly.
UNLIKE the one pictured above.

You mentioned installing the roller type layshaft bearing a few years ago. Was this (now failed) sleeve gear bearing replaced at the same time?

concours said:

View attachment 10967

Be careful, that your bearing fits properly.
UNLIKE the one pictured above.

You mentioned installing the roller type layshaft bearing a few years ago. Was this (now failed) sleeve gear bearing replaced at the same time?

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No, I didn't remove the Sleeve Gear / sprocket / Primary et al and couldn't see it. I assume I checked the shaft for play, spun it and listened etc but that was 7 years ago. The layshaft bearing was all I changed. In retrospect should have changed the bushes and O rings etc while it was apart.
I heated and pushed the inner race home on the layshaft. It may have been pulled out a during the failure. 'Speculating' as it got pretty hot the outer race of the Sleeve Gear bearing walked out of the case rubbing / pushing against 4th lay gear and the layshaft bearing inner race moved. I'll see when I measure the run out during reassembly if the shimming is still close.

The next gearbox I do is going to get a ball bearing on the layshaft.

swooshdave said:

The next gearbox I do is going to get a ball bearing on the layshaft.

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May I ask why you would do that?

Plastic cages in Norton gearboxes are not advisable if you are running gear oil. The cage will break up in time. Jim

Quote from DSM engineering plastics who make bearing cages for many manufacturers.

"Metal is used in the cages of these bearings due to strength and chemical resistance to hypoid gear oil," says Bill Burnham, Business Development Manager, Powertrains, at DSM Engineering Plastics. "This type of oil is typically quite aggressive upon most plastic materials."

comnoz said:

Plastic cages in Norton gearboxes are not advisable if you are running gear oil. The cage will break up in time. Jim

Quote from DSM engineering plastics who make bearing cages for many manufacturers.

"Metal is used in the cages of these bearings due to strength and chemical resistance to hypoid gear oil," says Bill Burnham, Business Development Manager, Powertrains, at DSM Engineering Plastics. "This type of oil is typically quite aggressive upon most plastic materials."

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Out of curiosity, would Redline Lightweight ShockProof be any different?