grinding noise from CARC when cold

My stelvio started a weird behavior, when cold, when driving away the first 2-3 meters it makes a grinding noise, It feels like coming from the Carc, not the clutch and it is also after releasing the clutch.
I park my bike and when I take it out it has to move 15 meters backwards before starting/ driving away.
After the first noise all is well. It does it for some thousands of km's. So when in motion all seems to go well.

More likely to be the driveshaft. One of the couplings may of shat itself.

CARC bevelboxes leak if the big bearing goes out and growl like a bastard on the over-run if the pinion nut dumps its preload but generally they are tough as old boots and don't break.

What does break is clutch plates in a short model run. What year is yours Paul?

Pete

its a 2008. I read from someone who had something similar, and that "turned out to be a bush inside that it fitted with loctite, and had come loose".
I found the oil that came out after 10k pretty grey. I've done 6k since(in 3 weeks) then I can take oil out to see how it looks like.
The shaft was out this winter and was fine in my hands.

Grey oil? That means some sort of Metalic degradation. It'll be steel or aluminium paste I'd guess.

Do you have a spare? If not I have little luggage on this trip, I could fling one of my many spares into a box and bring it with me on Wednesday. I could post it to you from England or France and it would cost not a lot.

Pete

Hi Pete I have no spare. It would be great if you can organize that. Isn't it to heavy? Up to 10 kg, it makes only 25 euro difference if I ship to UK or Australia. For 10-20 kg it costs 34 euro to UK, and 105 to Australia.

This trip we're travelling very light due to the fact that we're meeting two friends in Italy and we all have to squish into some preposterously tiny car! One small bag each! Our baggage allowance is quite big, more than adequate for me to be able to slip in a CARC I'd think.

What colour is yours? Black?

[quote="pauldaytona"]My stelvio started a weird behavior, when cold, when driving away the first 2-3 meters it makes a grinding noise, It feels like coming from the Carc, not the clutch and it is also after releasing the clutch.]

Paul, good to see that Pete can sort you out with a CARC. I always get the clutch groan from the Stelvio when she is cold but it is gone after the first 50 meters and never happens when warmed up, I put it down to a Stelvio quirk as it never happens with the GRiSO.

Pete are you visiting Ireland on your trip? If you are and are passing anywhere near Kilkenny, you and your other half are more than welcome to stop bye for a bit of Irish hospitality (grub,dark beer, light beer, whatever and maybe hit the pup for a pint)

Another oddball that drinks from the Guzzi mug is rare around here

Yes Pete a Black one. Going to GMG too? I'm curious what is wrong inside too.

Interesting. Very similar thing with my '14 GRiSO but mine is when the clutch is engaged. On a cold start, it moves away from standstill without drama. However, when the clutch is engaged coming to a stop, I can hear a rattling from what sounds like the CARC. Only ever happens once, in the first 50 metres or so. Only ever with the clutch engaged too (lever pulled in).

Never did it in the first 1,000kms and then one day the noise appeared. Weird.

Yup, we'll be at the GMG but only briefly. Jude and I are travelling with some old friends from Townsville in Far North Queensland for three weeks in Italy hopefully avoiding the big cities.

This is a big trip for us, we fly into LHR then visit some relatives and friends before heading north to Anglsea and getting the ferry to Dublin. We've got a week or so in Ireland and are heading up to spend the night with Dave Boyd and family before heading off to travel some of the Wild Atlantic Way, (We may well be in Killkenny during his time.) the we dump the car back in Dublin and fly to Tour in France to see friends, then on to Entrayges Sur Truyere to see a couple more relatives before heading to Italy.

We pick up our friends in Milan and then flee to the lakes! After that we have no solid plans apart from dropping in on Nelson and Jan in Barrea and loitering around in the Appenines making the place look untidy and eating and drinking too much.

We then drop the friends back at Milan and we head for Trieste and then go basically due north until we end up in Denmark where Juse wants to visit her ancestral pig farm! She is of solid Danish stock! Then it's back through Germany and the Low Countries, drop the car at Tours and hop on another Ryanair horror flight to Stanstead in the UK where we'll flee north to the areas we really love in Northumberland and on to Scotland. Finally we'll head back through the midlands and Shropshire before spending our last few nights in Cambridge where I grew up with some of our oldest friends.

A solid ten weeks of travel. We'll probably be tireder when we get back than when we leave!

Pete

Brent S wrote:

Interesting. Very similar thing with my '14 GRiSO but mine is when the clutch is engaged. On a cold start, it moves away from standstill without drama. However, when the clutch is engaged coming to a stop, I can hear a rattling from what sounds like the CARC. Only ever happens once, in the first 50 metres or so. Only ever with the clutch engaged too (lever pulled in).

Never did it in the first 1,000kms and then one day the noise appeared. Weird.

With any odd noises from the CARC it's worth pulling it off and peering down the seal holder around the pinion splines. You'll be able to see the peg nut that preloads the pinion bearings and using a small, thin screwdriver or seal pick you can see if the nut moves in relation to the pinion shaft.

The problem is that the nut only runs a comparatively light preload and is retained by a lockwasher. If it looses its preload then the nut starts moving in relation to the pinion and eventually it busts off the locking tabs on the lockwasher, the nut flogs it's threads out and the pinion can't maintain its positional integrity in relation to the crownwheel. Chaos ensues, followed by weeping at the cost of replacement.

The thing is that if you catch it before the nut unwinds or flogs its threads out you can save the unit. The problem is that the nut and lockwasher aren't listed as separate parts so you're expected to replace the entire reactive bridge! Luckily in time honoured Guzzi fashion the nut and lockwasher are recycled parts from an earlier model! Yes, the nut and its lockwasher are identical to the parts that hold the crank sprocket on to the crank of an old T3/LeMans from the 1970's and '80's!

Buy these. Strip the CARC, remove the seal holder and discard the buggered nut and washer. Clean everything thoroughly and make sure the pinion threads are clean and oil free. Install the new lockwasher, drip a small amount of 'F*#% off you're never coming undone again!' green Loctite on the threads and tighten the nut to 60-70 inch pounds! It's a collapsible spacer that adds the preload between the bearings. The nut isn't tight! Once torqued bend up the locking tab on the lock washer, let the Loctite set for a few hours and reassemble the CARC. If you've caught it early before any real damage has occurred you'll of probably salvaged the unit. I did this when mine dumped its preload some 20,000km ago and it's as good as gold.

Pete

Thanks Pete. Great advice as usual.

Not sure if the issue I have is the same as what Paul mentions. His appears to be when the driveline is under load, moving away from standstill. Mine is the opposite. Also, it's quite a possibility that the noise from mine is a clutch-related issue. Difficult to pinpoint the exact source of the noise. That said, it's the fleeting nature of the noise which is intriguing......it will happen on a cold start only which infers to me that it's something heat related (eg clutch) as opposed to anything which has come adrift which would presumably carry on all the time.

What year model? Although I've not heard of it affecting GRiSO's there was a run of duff clutches in Stelvios in 2012.

Typically if the pinion nut has, or is in the process of, dumping its preload you get a real 'H-O-W-L' on the over-run.

Pete

Pete, mine's a 2014. At times the drivetrain can whine a bit on the overrun, usually when plodding along slowly in traffic in 1st gear when you're feathering the throttle a bit. I'd call it a slight mechanical whine on decel as opposed to an obvious howling noise as such.

As this bike is my 1st and only Guzzi, I don't have any reference point to go by as to whether these things are anything unusual or not. All I can really do is keep tabs on whether noises etc get more noticeable or not.

Hmmmmm. Impossible to tell without hearing it but keep an ear on it. If it gets louder get it checked out.

Pete

My Stelvio and several others I have seen makes a horrible groaning noise from the clutch when it is first ridden from cold, especially after being parked in the damp. Goes away after the first couple of uses of the clutch. I have a theory that it is corrosion on the steel clutch plates.