Stelvio sump bolts sheared

[ducatiguzzi]

Hi All
I received my rollerising kit so as part of the clean up I want to drop the sump but 3 of the screws sheared on their way out. They were tight but did manage a turn or so before they snapped. Looks like differential material corrosion and it was the 2 front corner ones and the next so maybe weathered also. Has any one been here or can give advice? An engine out job may be on the cards but have never dropped a spine frame engine before just Tontis. Thanks

[Kiwi_Roy]

Just take an electric drill with a bit the same size as the bolt and drill the head off, it seems to go easier at low speed.
You may have to lay the bike on its side if you don't have a table.
Once you have the head off you will be able to remove the sump then it's just a matter of unwinding the bolt with a pair of vice grips.

[randy yocum]

It sounds to me like it's not the bolt head stripped but the bolt is broken off right down to the engine case. There is no way I would pull a Stelvio engine just to fix a couple broken sump bolts,the only way would be if a guy was holding gun on me,maybe,....it's a very big job. Kiwi_Roy had the right idea,lay the bike on it's side,center punch and carefully drill a pilot hole and use an easy out tool ,maybe soak the bolt with liquid wrench,could even add a little heat with propane torch.Some guys get lucky using a reverse drill bit which may catch while drilling and back the screw out.Good luck...

[Kiwi_Roy]

No, drill the head off then there's nothing holding the sump on, break an easy out in there and you are really in a fix.

[lucian]

If I'm reading this right, the heads of the allen bolts have already sheared off , so remove the remaining ones and drop the sump.  Hopefully the broken ones will have some protrusion beyond the bottom of the block. If so, some heat and vise grips may save your butt. If they are broken off below the blocks face then it's drills and extractors ,and not an easy thing to do while upside down in the bike.

[lucian]

after going to bed and not being able to sleep thinking about this dilema it came to me that the 8v has a sump spacer .So, after dropping the sump ,you could then remove the spacer which would fully expose the broken stud. You will need to get the additional gasket , but this should make it an easy fix.

Unless they truly sheared off below the block face itself, hopefully not!!

[Moparnut72]

Whatever you do, do NOT use an easy out. If you break it you will be in deep dodo. Heat and a left handed drillprobably the best. My former boss removed broken studs all the time. Tig welded a nut to end of the stud. With the heat they would just back right out. You could take the bike to a shop that can do this. It would take a load off your mind. My boss did it all the time on radial aircraft engine cases which wouls cost $1,000's to replace.
kk

[wirespokes]

I've heard that Alum will dissolve steel, but not aluminum. There are youtube vids how to do it, but haven't tried it yet myself.

[ducatiguzzi]

Thanks for your help guys. Ive advanced a little bit.
Yes they have sheared but if I take the sump spacer off I will have around 10mm protruding from the block to get a hold of. Does this spacer simply come away if I undo the 4 screws? I should have drilled the heads off, would have made it much easier as Kiwi_Roy mentioned. Easy outs are a last resort, I've had one snap on my in the past on a Honda head.... not fun to repair but got there. I'll order a spacer gasket and some screws no I think.
Thanks

[guzzisteve]

Besides the screws by the filter there should be a few recessed around the outside edge. From memory.

[Wayne Orwig]

Thanks for your help guys. Ive advanced a little bit.
Yes they have sheared but if I take the sump spacer off I will have around 10mm protruding from the block to get a hold of. Does this spacer simply come away if I undo the 4 screws? I should have drilled the heads off, would have made it much easier as Kiwi_Roy mentioned. Easy outs are a last resort, I've had one snap on my in the past on a Honda head.... not fun to repair but got there. I'll order a spacer gasket and some screws no I think.
Thanks

I think you have to pull the two oil pickups also to get the spacer off.
Maybe, I know I had to for some reason. Annoying when standing on your head to work under there, but not hard to do.

I would apply as much heat as I could to the broken bit. Even though that is backwards, then let it cool. Heat cycling it a few times like that can loosen it up. Apply your favorite thread loosening solvent when warm too. In the end, you of course want the BLOCK to be a warm as you can get it to extract the broken bit.
Avoid ez-outs. Apply anti-seize to the new parts.

[wirespokes]

What Wayne sez. I'd use a propane torch and heat up the stub - that'll transfer heat to the threads. Grab it with vise grips.

The idea is that steel expands at a different rate than aluminum, breaking the bond.

Another thing to keep in mind is not to force it out once it turns a little. Loosen a little, tighten. Loosen - back and forth. It'll move a little farther each time until it finally spins free. Think - driving out of a snow drift. I've seen it way too often where tires spinning but no progress. But if you go forward then reverse, a little more momentum each time, eventually it'll rock out of there.

[Bulldog9]

What Wayne sez. I'd use a propane torch and heat up the stub - that'll transfer heat to the threads. Grab it with vise grips.

The idea is that steel expands at a different rate than aluminum, breaking the bond.

Another thing to keep in mind is not to force it out once it turns a little. Loosen a little, tighten. Loosen - back and forth. It'll move a little farther each time until it finally spins free. Think - driving out of a snow drift. I've seen it way too often where tires spinning but no progress. But if you go forward then reverse, a little more momentum each time, eventually it'll rock out of there.

I do the same, and squirt a bit of aerokroil or equivalent onto the bolt before tightening back a bit. Almost like parallel parking in a tight spot, back and forth until you are clear.

[ducatiguzzi]

Thanks guys. I'm gonna try one night this week. It would have been tonight my my boiler packed up......another job to do. Grr!
I can see only 4 screws on the exploded diagram and as Wayne Orwig suggests the oils pick-ups will have to come off first. Ive got a small butane blowtorch with a fine soldering nozzle so I'll try that first along with squirts of plusgaz along the way. Cheers

[ducatiguzzi]

Got an update. The bike is currently on its side in my mates workshop. All 3 sump screws that had stubs all sheared flush after heat, soaking etc. We welded a nut onto one of them so plenty heat and it sheared as well. Its quite remarkable how solid the galvanic corrosion can hold them together. They are now drilled out and re-tapped back to 6mm.
The reason they are so bad is that the screws in question are the front corners and the one next. The screw holes are not blind but open to the elements from the top!! what a design! a nice little puddle of electrolyte. I advise anyone to seal this from the top with a blob of sealant or similar if its not too late.
Fun and games but getting there.
Cheers

[Antietam Classic Cycle]

The reason they are so bad is that the screws in question are the front corners and the one next. The screw holes are not blind but open to the elements from the top!! what a design! a nice little puddle of electrolyte. I advise anyone to seal this from the top with a blob of sealant or similar if its not too late.

At least 8 of the 14 perimeter bolt holes on an earlier Guzzi such as a Convert are open at the top and it's never been an issue. Sounds like Piaggio has been buying "butter bolts". Anti-seize and good quality fasteners are all that's necessary. Any moisture that collects in the hole should evaporate from engine heat anyway.

[Muzz]

We have a product down here called Lanocoat.  Basically solid sheep grease from the wool.  Don't know whether they add anything to it but we used it a lot in the engineering firm I worked in to coat dissimilar metals, especially stainless and alloy in a marine environment.

Not high tech, but still good stuff.  I use it a lot.

[LowRyter]

I hate Guzzi bolts.  They are the worst.

Replace with 12.9 grade.

[Rough Edge racing]

We have a product down here called Lanocoat.  Basically solid sheep grease from the wool.  Don't know whether they add anything to it but we used it a lot in the engineering firm I worked in to coat dissimilar metals, especially stainless and alloy in a marine environment.

Not high tech, but still good stuff.  I use it a lot.

   it's called Fluid Film in the USA....I spray the undersides of my vehicles to help protect against road deicing chemicals.

[Muzz]

   it's called Fluid Film in the USA....I spray the undersides of my vehicles to help protect against road deicing chemicals.

Fortunately they don't tend to use much of it here.   We just slip and slide.

[SurferDave]

I just had this happen to my Le Mans 3, one of the inner 10mm head bolts at the rear, all others off okay. Glad to learn I'm not alone!
I will take to Mario...

[ampm7]

I used to use Lanacoat on rigging screws (sailboat) and it is an excellent product as it resists practically all environmental pressures. Anti-seize (Hi-Temp) on the threads and Lanacoat to protect screw head and prevent water migration. I think they still sell Lanacoat at marine facilities.