GRiSO 1100 Drive with metal fragments inside

Hi guys!
I have chips, probably from a lock plate, in my final drive.
The lugs were broken (5mm) and then pushed out through the slots.

The metal pieces were pushed out of the final drive via the slots, see photos with lighting.

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You can still partially see the pieces inside, that can be moved around behind the slots of the metal plate.

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It is interesting that the chips only appear in the area of ​​the cardan tunnel, but not inside the housing of the drive.

Does anyone here have experience with something like this? Where exactly is this locking plate located or what does it secure?

Has anyone already repaired something like this?

I can't find it in the workshop manual or in the parts list.
Pictures are also not available.

BR
Havli

Yup, know it well. I’m about to eat but I’ll go into it a bit later. The lock washer secures the pinion nut and is essential for retaining the bearing preload.

Guzzi tells us the CARC Bevelbox can’t be rebuilt. I fart in their general direction!

OK, the bits of lockwasher are almost certainly from the one that secures the pinion nut. The reason there are no bits of it in the main chamber of the cases is because there is a seal preventing it from getting there.

I'm assuming you are aware that the mesh of the crownwheel and pinion gears is set up very accurately by shimming and that it is also vital that the alignment between the gears remains exact and isn't lost in any way.

We'll get to all that later but the first thing you will need to do is press the reactive bridge, (The casting that contains the crownwheel and pinion.) out of the other case. Once it is out you will be able to spin the pinion and examine the pinion and crownwheel teeth. If they are damaged in any way there is no point in going any further. They are scrap and it's time to look for another bevelbox. If they are undamaged though with no chipped or broken teeth and no discolouration then we can proceed to how to fix it up and get it working again.

I'm assuming once again that it started making a noise? Most particularly on the over-run?

Hi!

Sounds like a plan, i will start to further dissamble the drive.
Do you have any pictures of it, on a further step than mine?

Regarding noises or so, there was nothing at all, i stepped into it by accident checking the seal of the Gearbox.

Maybe i´m lucky!

Have a look at this and ask questions.

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No need to disassemble the crownwheel or pinion from the reactive bridge if the teeth of the gears look good.

You rock, THX!
Will do like described!

Once you have checked the gear teeth we can move on to fixing the lockwasher/preload issue.

Hi!

According to the Guzzi-Guideline, i can simpli seperate the LH-siedecase with heat, the big bearing will stay at the mounting plate.
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For dissambling and checking the teeth of the pinion, it shouldn matter if i let the bearing at its place, right?
So i dont need the 30t press right now (but in case i can access one).


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After getting away the RH/LH-cases, i only need to get out the smaller bearing, holding the shaft of the pinion (yellow arrow).
All other bearing will get after that without issues, am i correct?

I just want to confirm, if my plan has a chance to work the way it is

If you go that way the seal is definitely sacrificial and should be prised out prior to the heating.

Either way is fine, as long as you get to see the teeth.

Once you can ascertain the teeth are OK, or not, we can move forward.

Almosr done!
How did you get the ring off?
Did you manage to loose it with hammer, drill a hole or something.
Its really tight and it wont move at the thread.

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The part the screwdriver is pointing at is the inner race of the bearing. There is no need to disturb that part of the unit at all. You can see the pinion teeth sufficiently to assess if they are damaged simply by turning the unit over. You don't need to disassemble it. Now you'll need to source a new tab washer which will mean a trip to the SKF dealer.

oh, damn thx!
I tried multiple times to move it, but i think no harm done!
Teeth look good as far as i can tell, both pinions are okay.
But to be honest, i would rather dissamble it in order to clean it.

How can i access the tab washer?

Don't! Doing so will really be making a rod for your own back. Now you have removed the peg nut from the crownwheel spindle you have already introduced another piece of guesswork into the puzzle. I'll explain a bit later but as long as the teeth are fine, leave the crownwheel and it's bearings alone.

Thx Pete, i'm happy that it seems to be okay so far.
I will change the bearings as well, i dont like the way they are moving, so no harm done

What kind of washer do i need, do you know the exact type?
Where can i access it? I'm guessing by dissasamling the unit where the Kardan goes in!?

Dont know how its called in english, but its this part i need to open up,  right?[You must be registered and logged in to see this image.]

Sorry for the many questions, i just wanne do it the right way in order to become a good mechanic

The reason the crownwheel bearings are moving 'Oddly' is because when you removed the ring nut you released the preload on them so the bearings can now move in the race meaning the crownwheel and its spindle can tilt. Both crownwheel and pinion are shimmed for depth engagement and while all bearings are made to ISO standards there is no certainty that other bearings won't require the depth of engagement to be re-shimmed. Since Guzzi claim that the reactive bridge is a non serviceable part these shims are not available so you would have to get your own made. Also, are you familiar with the process of setting up the mesh and backlash on spiral bevel gears? It's not particularly intuitive and the results of getting it wrong will be trashed gears in a couple of kilometres of riding. The bearings used in the CARC bevelbox are massive. There is no evidence of damage to the gear teeth. I STRONGLY recommend that you follow the instructions I will give you about replacing the ring nut and lock washer on the crownwheel spindle and DO NOT attempt to disassemble the unit any further than you already have.

okay, no further dissasamling!
I will follow your instructions 100% in order to get my GRiSO whole again!

Next thing, to get a new tab washer!
What kind of an where to build in?

Br
Havli

Havli wrote:

Dont know how it's called in english, but it's this part i need to open up,  right?[You must be registered and logged in to see this image.]

Sorry for the many questions, i just wanne do it the right way in order to become a good mechanic

Yes, this is the part you need to remove to access the pinion nut. To do that you need the special peg socket that fits the seal holder which is the part in that photo inside the neck of the reactive bridge. It is locked by a G clip whose tail engages with one of the slots in the outside of the casting and once that is removed the special peg socket can be used, as seen in the pic in the first link about stripping a CARC with the much younger me trying to bust my chuffer valve getting the seal holder undone! I've since learnt that a bit of heat helps a lot to loosen it up by expanding the neck of the bridge, which is aluminium, so it expands more than the steel of the seal holder.

okay, that will take time to build that tool!
Thx Pete, i owe you!

Havli wrote:

okay, no further dissasamling!
I will follow your instructions 100% in order to get my GRiSO whole again!

Next thing,  to get a new tab washer!
What kind of an where to build in?

Br
Havli

For the crownwheel nut you will have to get a lockwasher of the correct size from a bearing shop. I believe they are a specific SKF product so take the ring nut you have removed to the SKF dealer and explain you need a lockwasher for it. Alternatively measure and look here.

Link

You are also going to require a nut and lockwasher for the pinion. But I'll cover that a bit later.

heat helped a lot, whats next?
Wondering, that i cannot find any metal pieces ...[You must be registered and logged in to see this image.]

ah, found some [You must be registered and logged in to see this image.]

.

Has the pinion nut got any threads left inside?

okay, now i got it!
I checked for peaces behind the first bearing, everything seems clear here :-)

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The washer is securing this part here?
At least i cannot see anything else worth staying in place

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looks good to me, any objections?

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