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Is this a main oil seal leak?

notasweetman said:
If anyone could let me know some numbers of A5 engined Stelvios affected, I'd be very grateful!

PM sent with my engine no and some other info

I'll fully support you on this where I can.
 
Sorry to be so long with this reply. I've just posted elsewhere that I've had my oil leak fixed, out of warranty, with parts supplied by Guzzi (admitting liability for manufacture errors) but that I've had to cough up £600.00 for labour. I put in a new clutch plate while the bike was apart at my own expense because while it seemed ok, there was oil contamination to the outer edges and I didn't want to have the bike stripped to such an extent again! (And the clutch plate was cheaper than I thought - £28.00! - someone said that Citroen 2CV has the same plate???????)

The main bearing was faulty (see pic). I haven't found anyone else with this problem so I hope it's a one-off. Plus the bearing carrier bolts were too long - as discussed earlier - and Guzzi paid for the main seal.

My point is that if you have an early A5 engine that develops an oil leak please get someone to have a good look at the cause. My mechanic let me have a peek at 5 service updates which Guzzi has sent out which cover possible causes of main oil-seal leaks - all of which result from some kind of manufacturing failure.

That said - during the 7 weeks my Stelvio was out of action I was besieged and battered by friends telling me to 'wise up and get something more sensible & reliable'. Not a chance. I love my Stelvio. Love it.

Moto Guzzi Stelvio repair 91
 
notasweetman said:
The main bearing was faulty (see pic). I haven't found anyone else with this problem so I hope it's a one-off. Plus the bearing carrier bolts were too long - as discussed earlier - and Guzzi paid for the main seal.

Any idea what caused the main bearing damage?

Mine has developed a small leak. I have check everything a dozen times and the only place it can be coming from is the rear main area. I hate that, as it is about the most buried spot on the bike. :angry:

I'm going to let it leak until the holidays at the end of the year when I will have some time to work on it.
 
Hi, Wayne,

As I said, the factory has issued the oil leak appendices that my mechanic showed me. I'd try to get sight of them from a friendly dealer - they shouldn't be secret, should they? My main bearing fault could well have been there from installation. Looking at it, it seemed to be inherent, rather than resulting from load, stress or usage but without proper examination we'll never know.

MG gave me no chance to keep the suspect parts and insisted the dealer return them as soon as they received the new ones. I can see why, but surely I bought the faulty parts when I bought the bike, so they are mine, irrespective of MG's admission of guilt by replacing them out of warranty? That bit sticks in my throat a bit. At least I got the photo.

Watch your leak. Mine was fine for a month or so then dramatically increased to the point I could see splashes on the rear after a run. As you say, the source is buried about as deep as you can go in the bike. Good luck.
 
fatal said:
If you have no luck with Moto Guzzi, how about using the 'sale of goods act', claim from the supplying dealer, surely it is reasonable to expect a leak free engine after only 2 and a bit years, and 12000 miles, have you taken advice from your local trading standards dept?


Eventually a result.

Did the sale of goods act letter with a little help from you guys on here and a collegue at work in the supply chain group.
Sent the letter mid Jan 12, couple of phone calls and got a check foir the full value yesterday :D :D :D

Paid by the deal not by Guzzi, so big thanks to Robinsons of Rochdale, despite them not being Guzzi dealer anymore, for doing the right thing. :D
 
Rather than removal of the engine and transmission from the frame and reinstall. 2 day job - Joy Joy! I decided to applied some American ingenuity to this Italian weakness for adequate engineering. This apparatus I named an oil catcher. It is sealed to the back of the engine with Loctite RTV 598 Silicone and a bolt on each side. The 1/8 wide slit will catch the oil and retain it in this 1" square thin wall piece of tubing. Holds 4 ounces. Has a drain on the same side as the kick stand. Will serve the purpose so I can continue ride this season and do the repair during next winter. When going gets tough the tough solve problems! I hope? I'll let you know how this temporary fix functions. [youtube]http://www.youtube.com/watch?v=xDVWwm8X5s4[/youtube]
 
I have been reading this forum (amongst others) avidly over the past few weeks. I seem to be another victim of the early 8V engineering fault of these beautiful machines. Below is an email I have sent to Moto Guzzi Australia, just wondering what they will say. I don't know whether to simply replace the gasket, o-ring and seal and machine the securing bolts/dowels shorter, or go for the upgraded flange and re-install without the gasket as recommended. I was going on a 1000km road trip to Byron Bay at Christmas on the bike....looks like I will be taking the car.:(
Craigozzie
---------------------------------------------------------------------------------------------------------------------------------------------------------------
Hi guys
I am wondering if you can help me. My 2009 Stelvio has developed an oil leak coming from under the bell housing. At first we thought it may be simply at the rear of the upper sump gasket so we replaced the upper and lower gaskets etc. $670 later and it was still leaking.

The only other option then was a leaking main seal. We have taken the starter motor off and it is indeed oily inside the bell housing, leaking engine oil from the engine side, not getting on to the clutch plates.

I have spoken to a few Guzzi technicians and they have mentioned a common problem with the first 8v motor with leaking main seal due to the bolts and dowel securing the flange being too long and preventing it from tightening enough, causing it to leak after a period of time. My bike has done 30,000 kms. There are quite a few mentions of this over the internet. Below is a link to one of the forums.

https://www.guzzitech.com/forums/threads/is-this-a-main-oil-seal-leak.6161/

What I am wondering is if you have come across this before and what the best fix is. One technician is telling me to machine the bolts and the flange and replace it without the gasket. If I replace just the gasket and seal and O-ring it will probably do this all over again. I guess I am just looking for the best direction to head in and your advice. (I do believe that this was never a factory recall?) This is going to be very expensive for me after it is all finalised. Hoping you can help.

Regards

Craig Ostini
 
If the bolts are too long, then shorten them. You only need five threads to engage for security. I'd still use the gasket and o-ring. I'd also install with blue loctite (242).
 
On some of the early Grisos and Stelvios, the bolts were simply a little too long, They bottomed out and the gaskets/o'rings did not seal. You can shorten the bolts , or add a thick washer under the bolt heads. I think it is just the two bottom bolts.
On some, the machining for the o-ring was too deep. The o-ring did not have enough 'squeeze' on it to maintain a seal. On those, you normally would need to replace the entire rear bearing carrier.
Mine had a leak under the o-ring on the bolt where they bore the block for the shaft that drives the cam chains.
 
Craig, in addition to above... Being that it's an '09 w/30km's, I suspect if you are fortunate, they will cover the parts per an earlier post. I completed my fifth rear main leak issue about a month ago. This time on an '09 Griso 8V with 33k m/53k km. All of the main bearing flange bolts were again finger tight. The bolts/threaded pockets were all good/correct lengths, as was the o-ring pocket.
It was leaking both around the gasket and the rear main oil seal. When I pulled the rear main flange for the seal replacement, the bearing had the same markings as posted above (wear marks on the surface), so I replaced it. Upside was there was (just) one rear main in stock in the U.S.
Keep us posted on what you hear from them and/or what the end result is.
 
OK guys, going to do some thread mining here........my '14 Griso 8V has an oil leak in exactly the same place as the pics in the OP. The bike is only 12 months old, and with only around 3,000kms on it. It's still under warranty, so I'll be taking it back to the dealers fairly soon. I was hoping all this time that it wasn't a rear main seal leak, but looking at the pics above, I now think it almost certainly is.

I would have thought that a '14 model with so little mileage would be largely immune to a leak of this type, so I'm pretty disappointed to be honest. Has anyone else had experience with a rear main seal failure on what is essentially a new bike?

I'll book it in with the dealer and post a few updates if anyone is interested.

Brent.
 
Hi Brent.
My brand new Stelvio 2014 which I bought in March 2015 had the same oil leak at 1500 km on it.
The flange had to be replaced by dealer. The job took 25 days in total.
Image Image
 
Hybal. Sorry for the belated reply. The leak on my bike is very slow. In fact, only once has there ever been a drop of oil on the garage floor from mine. Its just the rear sump area getting damp with oil, and you can see half a droplet forming which takes several weeks to appear after I clean the bike. The dealer appeared somewhat reluctant to do much about it, since they cleaned the area and took it for a ride, but couldn't trace the source of the leak given how slow it is.

Was yours leaking badly?
 
Hybal. Sorry for the belated reply. The leak on my bike is very slow. In fact, only once has there ever been a drop of oil on the garage floor from mine. Its just the rear sump area getting damp with oil, and you can see half a droplet forming which takes several weeks to appear after I clean the bike. The dealer appeared somewhat reluctant to do much about it, since they cleaned the area and took it for a ride, but couldn't trace the source of the leak given how slow it is.

Was yours leaking badly?

In my case it was much worse than one drop per day. But it started slowly and became worse and worse. And it finished by real leaking oil from plugged hole after ride. You can see it here: IMG 0897
 
Hybal, so was the end problem a leak from the rear main seal, or from one of the welch/sump plugs as per your picture?
 
Hybal, so was the end problem a leak from the rear main seal, or from one of the welch/sump plugs as per your picture?

The problem was wrong o-ring groove at output flange. They had to replace the flange.
The leakage was at o-ring but oil came to clutch. So finally when stopped - oil dropped from the bottom of engine and from plugged hole too.
 
New to the forum, just purchased a 2009 Stelvio a week ago from a dealer. Super low miles, very well kept with roller conversion done.

Problem is oil leak at the rear engine/bell housing and at the left rear sump area near the center-stand pivot(?). Also noticed a little (fresh?) oil in the clutch inspection opening, although its not super oily in there.

I checked the oil, it was clearly over filled (over max), drained about 1/2 a quart to get to mid-way on the dip stick. Also checked the airbox, no oil there. The origin of the leak definitely appears above the sump gasket. No problems with the clutch noted.

Slowly leaks about 10-15 drops after being ridden, I'm guessing its dripping while riding too. I have ridden it a few times after correcting the oil level, with similar results....drip, drip, drip.

After reading (alot), sounds like this might be a rear main or flange seal?

I have some good mechanic skills, but not a pro. I've done lots of suspension work, water-pumps, changed clutches and brakes, some electrical... but splitting the drive train to get to these seals seems like a big deal! I usually like to do my own repairs mostly because I don't trust people working on my stuff. I have serious mechanic trust issues.

The dealer who sold me the bike is willing to take look at it but it sounded like it may take awhile before they can get to it, they are a Guzzi dealer which is good, but the time frame may be unpredictable. They have ONE MG mechanic and they service lots of BMWs.

Questions:
Is this a pretty easy but labor intensive project? Should I go for it? If so, where can I find resources/pictures?
Or, should I just wait it out and let my bike sit at the shop for some unknown amount of time and have a "pro" deal with it?

I'm totally bummed. This Stelvio is AMAZING, rides and runs great and I'm willing to put some time and money into it but don't want to start off on the wrong foot.

Any advice?

MG leak 1 MG leak 2
 
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