They make something so strong it's basically bomb proof and then..........

[Bill Hagan]

On the road -- in a cage, not Guzzi  --in Erie, and just catching up with the forum.

As for this thread, BTDT with my Norge.  

I did NOT stop in time.  Paid the price.  

Well, Guzzi did as it was still under warranty.  Only extended, tho, because of "settlement" following  oil-pump failure.  Yes, it was rocky beginning. 

What a great example of "for want of a nail," etc. 

Bill

[Rolf Halvorsen]

Hi Pete and the rest of you.

 

A few years ago I was given a CARC that had some problems. I asked for this because I wanted to open it and try to find the reason why it had this damage.

After a full dismantle - I saw that the pinion was damaged - and from a teeth from the lockwasher. 

I leant also that you could not buy a new pair of pinion/crown wheel.

When you Pete talk about the need of tightening the locking nut with high torque + Locktite - I come to think I remember that there is no distance cylinder (+ shims) between the 2 pinion conical bearings. 

If you compare this design with the old bewelbox design - they had the distance cylinder + a number of thin shims, so that you could apply a high torque on the pinion locking nut.

My problem now is that you should not use preload on 2 opposite conical bearings without theese movement limiting cylinder and shims. That is why the factory has choosen another solution with only a lockwasher. I agree fully the need for Locktite - but I am not sure about the torque.

Am I remembering wrong?

Rolf

[pete roper]

Rolf, on the contrary, I mentioned a very low torque for the nut. This is made particularly confusing because the manual, written in usual, rather vague, Guzzi fashion does mention a very high torque for a nut in the CARC but this is in fact not one of the crownwheel or pinion nuts, (They aren't mentioned because the whole reactive bridge is a non repairable item according to them!) that high torque is in fact for the seal holder which also compresses the outer races of the pinion bearings and seats them.

[Rolf Halvorsen]

Pete

Then I can agree.

This locking design is not the best I have seen around. But the real reason for one of the locking tabs to break loose - and make trouble elsewere - is that when you apply some "high" torque on the bearing locking nut - then you will apply some "high" friction on the lockwasher.

In my case it was the locking tab inside of the lockwasher that had broken loose - and sometime later made trouble.

Whenever I have this kind of lockwasher - then I apply some grease on it to reduce the friction from the nut. This friction reducing method is not mentioned anywhere which I have seen.

Rolf

[Lucky Phil]

8 minutes ago, Rolf Halvorsen said:

Pete

Then I can agree.

This locking design is not the best I have seen around. But the real reason for one of the locking tabs to break loose - and make trouble elsewere - is that when you apply some "high" torque on the bearing locking nut - then you will apply some "high" friction on the lockwasher.

In my case it was the locking tab inside of the lockwasher that had broken loose - and sometime later made trouble.

Whenever I have this kind of lockwasher - then I apply some grease on it to reduce the friction from the nut. This friction reducing method is not mentioned anywhere which I have seen.

Rolf

I personally use moly grease here. The rational for locking washers with tabs isn't to prevent the loss of torque on the nut it's to retain the nut and stop a total catastrophe until the issue is isolated and that's often through routine maintenance checks. They are old and somewhat unreliable technology. Personally I think Loctite is a far better way to go on most stuff like this with the lock washer as the backup. I've seen the internal tab on the lock washer broken or partially broken many times during the torquing up but you tend not to notice unless you put a witness mark on the lock washer and the housing when you torque up. That way you can see if the internal tab has deformed or broken.      

Ciao

[docc]

Ah, okay, so this is the same type nut/ "safety" washer that anchors the V11 gearbox input hub?

[pete roper]

Yup, same same, just a different size. These nits and washers ar a generic SKF part available at most decent bearing factors.

 

[docc]

23 minutes ago, pete roper said:

Yup, same same, just a different size. These nits and washers ar a generic SKF part available at most decent bearing factors.

 

Thanks, Pete! Now I understand what you mean by a "peg socket." Those are commonly available as a generic SKF, as well?

[pete roper]

1 hour ago, docc said:

Thanks, Pete! Now I understand what you mean by a "peg socket." Those are commonly available as a generic SKF, as well?

Yup. I just bought one for the crownwheel nut.

[Rolf Halvorsen]

In my opinion theese SKF-tools (KM 1, 2, 3, etc) has not the perfect form. Put the pipes in a lathe and remove the front 2-3mm. Thereby they will attach the peg screws better. And sometimes I had to reduce the outher diameter to get it into the house to attac the nut.

And for the old 5-speed Tonti gearboxes - SKF did not had that dimension - so I ordered about 100 directly from the SKF tool factory to be produced according to my drawings.

I hope that Pete still have them.

Rolf

[pete roper]

Yup I do, they've been invaluable Rolf.

[Rolf Halvorsen]

Back to the original topic.

There must be a design error to use this lockwasher in this position since more than me have "found" broken off lock tabs INSIDE of the CARC - where this piece of steel has caused critical damage til the pinion/crownwheel and bearings.

I come to think it would be better to remove this lockwasher totally or replace it with an ordinary washer. This plus loctite only of the pinion nut only.

It is not always belt AND suspenders are such a fine combination.

Rolf

[Randy]

On 3/23/2021 at 6:08 PM, Rolf Halvorsen said:

Back to the original topic.

There must be a design error to use this lockwasher in this position since more than me have "found" broken off lock tabs INSIDE of the CARC - where this piece of steel has caused critical damage til the pinion/crownwheel and bearings.

I come to think it would be better to remove this lockwasher totally or replace it with an ordinary washer. This plus loctite only of the pinion nut only.

It is not always belt AND suspenders are such a fine combination.

Rolf

Do you think the Loctite alone without the washer is enough to keep it from loosening back up?

[Rolf Halvorsen]

Well, I would try to find a thin plain washer with the approximal inner and outher diameter + loctite on the peg-nut. It should work without the washer of some kind - but I would be happier with a plain washer.