Carc / Swing arm leak

Developed a small leak that I'd like some help to rectify. Any advice of how to fix would be appreciated. It seems to be in an odd place...
It's leaking from the rubber connector that holds the break line and speed sensor cable. I took the entire swing arm apart 2 years ago to service the bearings. No issues since. I didn't even think this area of the swing arm had oil in it.....
First picture shows where the oil lands on the ground but the other show the culprit, with the last one showing a drip of oil on it.
Thank you.
John


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First picture looks like something has dripped onto top of the CARC (or it's a trick of the light) or oil has burped out the bevel box vent ?

Anyway...
- is it running down the brakeline/sensor cable from leak further forward (is there oil traces on these)?
- is it running back from brake caliper ?
- what does it feel & smell like ?
If it's only appearing underneath at that spot, I'd guess it's bevel box oil From back) OR gear box oil (from front) coming out of the CARC joint with swingarm.

Hi Paul,
It's coming from the bottom of the swing arm. It's definitely carc oil although the level is full. Small leak at this point. It's not brake fluid. A colleague (Cognosticator) and I think it must be the "dust cover" inside the CARC thats leaking and letting oil through to the swing arm. It then comes out the bottom on the swing arm where there is a penetration (clip) that holds the brakeline and speed sensor cable.
Which is all bad news if this is the case. We'll have to take the whole things apart to get a new gasket on. Part number is GU05358330 and shows on page 221 (of 259) in my shop manual.
Don't know if we're capable of all of that................

Had one like that last year, he had bigger problems. Nut on pinion had backed off, back & forth had a bit of oil drift.
At the shop I had one also, was a pinched vent line by battery. That had oil burping out of trans rear seal.
Dry inside, you should be able to see where it's coming from.

Ed Cook at AF1 is telling me that GU05358330 is just a dust cover and holds back no oil......which seems different that what I was reading on a thread at Wild Guzzi from 2017. A very confusing situation. Plus, it cost $331 US....

Most likely the pinion seal on the bevelbox but it might be the output shaft seal on the gearbox.

Pull the evil box off and peer down the pinion through the seal holder. If it's wet around the pinion nut it'll be the pinion seal. When replacing it make sure the nut hasn't come loose and use a few drops of Loctite 290 'Super Wick In' on the threads without undoing the nut before reinstalling the seal holder.

If it shows signs of oil having run down the swingarm from the gearbox end it'll be the gearbox output shaft seal. Pulll the swingarm and replace.

Been there.

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Thanks Pete and Beetle!
I suspect my problem is from the CARC end as there are two penetrations on the swing arm and only the one on the CARC end leaked. And just like Beetle, just a drop here and there. I checked both oil levels and both were full to the top. The leak has been minor.
Pete, you you tell me the part number I need and how troublesome it is to deal with? I suspect you have to split the CARC open etc???
Thanks again.

Thanks Pete and Beetle!
This is swimming in the deep end for me. We have a MC dealer where I live now that has been an Aprilia dealer for a while and has added MG. Some of my riding buddies trust them so I'm about to find out if this is in their wheelhouse. But, I'm armed with your diagnosis and part numbers I've looked up and some schematics. I'm sure over kill...I'm going to talk to them tomorrow.
Thanks again.

The problem with the Pinion seal is that you need to remove the holder which in turn requires the front boot to be removed. The boot is retained by a supposedly single use clamp and to get at it you are supposed to split the CARC cases.

Now Michael has got very good at teasing the clamp apart so he can re-use it. I never had much luck with that so I always split the cases but after it is off you need a special tool to undo the seal holder after removing the G clip that retains it.

If you split the cases you can replace the single use clamp with one of the straps used to retain the boots on CV joints of front wheel drive cars. If you don't you have to get clever like Michael!

I think I might of done a photo essay on the procedure? Have a look in the tech section.

Edit.

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While this was actually about bearing replacement the front seal holder removal is covered too! Just look at the handsome young man removing the seal holder!

Thanks Pete. I’ve printed out pictures and tutorial to take to the shop so hopefully this will be done correctly. Depending on how busy they are, I may (with the help of my colleague) take the carc off and just take that to them.
Will let you know the outcome and many thanks again!

The guys in Savannah that sell Aprilia's are selling Guzzi's ???

Yes Steve they have been for a few months now. I went there yesterday and spoke to their parts and service manager and ordered the pinion seal. He told me Piaggio/ Guzzi had them buy about $4,000 of special tools to support MG bikes. It’s encouraging that a new dealer is coming on board when it seems like many have checked out. They had 6-7 V7’s and an 850 and the V85TT.
Thanks to this site, there isn’t much I need them for except jobs like this one. I hope they are successful and would be great if MG would come out with a new bike I’d be interested in buying to add to the GRiSO.

$4K for Guzzi tooling? If they do 'Prillas they'd already have PADS. I can't imagine what they had to spend $4K on? I've got a huge toolbox full of 'Special Tools' for Guzzis going back decades and yes, they're probably worth north of $4K US but for a 'Start-up' operation? The words 'Off' and 'Fuck' spring readily to my tongue, but not necessarily in that order......

Pete,
Maybe that was just to make me feel like they know what they’re doing.....I can look gullible.

If they get in trouble, the TechRep Brad is over here by Athens.

Pete and Guzzi Steve,
Would you have a ball park guess of what is a reasonable charge for this operation? I’ll be asking tomorrow when I drop it off.

(sigh.)

John, this is an almost impossible question to answer.

While for someone with a lot of experience like Steve or myself it might seem easy and pretty rudimentary for someone unfamiliar with the operation it will obviously take considerably longer, and it's the time factor that is going to determine the cost.

Even different individuals may have different abilities which can effect the cost. As I have said before Michael has got very good at cunningly removing the boot from the front of the pinion seal holder so he can replace the seal without splitting the CARC cases. I've never been able to do that and that alone will add at least an hour to the job!

It's the time factor that will be the major cost component. If it's the pinion seal then the wheel and brake caliper need to come off. The Speedo sensor be unhooked and then the bevelbox removed.

Then the seal has to be replaced which, even if you're as smart as Michael, takes some time as it's a fiddly operation through the neck of the bevelbox. If you're spud-thick like me and you split the case it takes longer. A lot longer!

All I can really say is that when I do one, splitting the case, it's usually about three hours. When Michael does it it takes about 1 & 1/2 to 2 hours. People like Michael!

Apart from that there are parts, but usually just a seal and, if the box cases are separated, a couple of boot straps, a bit of oil and we bung on a bit for 'Consumables' like grease, Threebond, Loctite etc.

Bottom line is it's not a hugely expensive job. As long as there are no 'Hidden Horrors' it shouldn't cost much more than $500AU and that is an upper end estimate.

If the swingarm is pulled to get at the gearbox output shaft seal it's probably less time but if the swingarm is coming off you'd be insane to not get them to re-pack the swingarm and shock linkage bearings. Just do it. It's only another hour or so.

One thing I fear happens a lot nowadays is that shops will quote ridiculous hours for a job hoping that the customer will baulk at the cost and 'Trade In' their bike on a new one. It's no a philosophy I'm wild about. I'd hope anyone sensible wouldn't go down that path. Especially with a GRiSO...

Pete,
Everything you've described makes perfect sense. I've taken the entire thing apart before with a friend (not the bevel box) to grease the things needing attention that you've identified for us. It took us about 4 hours. To your other point, I don't want to hear some ridiculous estimate or even worse, no estimate. I'm not going to trade her in on a V7.............
I've assembled a step by step "book" on what needs to be done, thanks to you and I'll have a chalk talk with them. I feel like I could pull this off on my own if I had to. Going in tomorrow to drop her off and chat. Very much appreciate all your help.
John

If it comes from the gearbox I would recommend to give this a try:
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I had succes with this on my Cali and the V11.

If you want to go the 'swell the seals to close the leak'; you could chuck additive in the bevel box as well BUT it'll only work if the problem is seal shrinkage (aromatics leaching into the lubricant) in the first place.

....and there may be side-effects

If they tell you 5 grand for new box, send it to Pete !!

Thanks everyone.
Since Pete mentioned putting locktite on the nut that holds the seal in place, it makes me wonder if the nut has come lose and that's why it's leaking. So I really don't want to put an additive in. I think it needs "open heart" surgery unfortunately.
And, it could be leaking from the drive shaft side, although I feel that is unlikely.

Pete,
What kind of special tool is needed to remove and replace the pinion seal nut?
Thank you.