Sealing the Swing-Arm Boot on V7 Stone

[SmithSwede]

Since I have a trip to Alabama and then Cedar Vale coming up, I changed my rear tire this weekend.   Pulled off the bevel box to lube the splines, and about 3 ounces of water spilled out of the swing arm tube.   Hmmm.   That's probably why my final drive oil was milky green.   No doubt this water came from a ride I took last month when I rode for several hours in an absolute downpour that just wouldn't let up. 

This is about the third time I've experienced this water intrusion into the swingarm.  So I took a very careful look at the rubber boot this time.  It was perfectly sounds, with no holes or tears.   

But the internal snap ring that secures the boot on the inside of the swing arm does not make anywhere close to a complete circle.   There is about 30 to 40 degrees of the boot that is completely uncovered by the ring.   And sure enough, I could easily push in a probe in this area.   On my bike, this unsecured area is at the top, 12:00 on the clock face. 

I thoroughly sealed up this area with silicone sealant--will see how this holds up.  Also wondering if maybe a the better solution is to install two snap rings on the inside, with their gaps oriented in different areas.

Anyway--it appears these boots are not fully sealed, and will leak if you ride long enough in the rain. 

[sib]

Since I have a trip to Alabama and then Cedar Vale coming up, I changed my rear tire this weekend.   Pulled off the bevel box to lube the splines, and about 3 ounces of water spilled out of the swing arm tube.   Hmmm.   That's probably why my final drive oil was milky green.   No doubt this water came from a ride I took last month when I rode for several hours in an absolute downpour that just wouldn't let up. 

This is about the third time I've experienced this water intrusion into the swingarm.  So I took a very careful look at the rubber boot this time.  It was perfectly sounds, with no holes or tears.   

But the internal snap ring that secures the boot on the inside of the swing arm does not make anywhere close to a complete circle.   There is about 30 to 40 degrees of the boot that is completely uncovered by the ring.   And sure enough, I could easily push in a probe in this area.   On my bike, this unsecured area is at the top, 12:00 on the clock face. 

I thoroughly sealed up this area with silicone sealant--will see how this holds up.  Also wondering if maybe a the better solution is to install two snap rings on the inside, with their gaps oriented in different areas.

Anyway--it appears these boots are not fully sealed, and will leak if you ride long enough in the rain.

Thanks for the great pointer.  Installing two snap rings with their openings staggered sounds like an excellent idea.

I avoid riding in the rain.  What can I say, I'm a wimp, I also avoid riding in the snow, ice, off-road, and in seedy neighborhoods.  But, the next time I do get caught in the rain, I'll try to remember to inspect under the boot.  For now, I'll order up a spare snap ring or two.  Thanks again.

[SmithSwede]

Has anyone tried the 2 ring solution?  Is there a better solution? 

I've never taken the boot off.  So I'm not sure if the snap ring fits into some kind of recess in the swing arm.

I'm also not quite sure how one goes about installing or removing remove these snap rings.   If the snap ring has a lot of tension, then that could be a real bugger of a job---especially since you might be fighting to install the snap ring while at the same time trying not to tear or poke a hole in the rubber boot.

Any tips from the pros on how best to install or remove the internal snap ring for the rubber boot?

[Chipmaker]

I dont know about a stone.On my old V700 I had to replace the boot. When i sealed it up at room temperature,then road it and the temp.got warm the boot swelled uplike a ballon.I then let the excess air out and resealed it hot.This worked good untill it cooled off,then the boot was sucked in against the ujoint!So I ended up venting it with a small hole in the lower part of the boot.

[BMCMOTO]

Chipmaker's experience is interesting.  I would have thought that Guzzi would have continued to vent both the transmission and gearbox as on the earlier smallblocks; Brevas and such, am I wrong in thinking that?  If both are vented shouldn't that have prevented Chipmaker's experience, the inflation and deflation of the boot?  Curiosity on my part, have no dog in this hunt, just thinking that a breather somewhere might be plugged or pinched and/or need moving to higher location. 

Brian

[DaSwami]

Well that's one item that can be argued that negates the advantage of a shaft drive. At least in the V7.  I try not to ride in a downpour but sometimes ya get caught.  Sounds like a design flaw or that the boot sealing is an afterthought?

[SmithSwede]

On my 13 Stone, the transmission and bevel box are both vented. 

I think what Chipmaker may be referring to is the fact that the airspace in the swing-arm itself is not vented.   That space is outside of the transmission and bevel box seals, and does not have a separate vent, other than what the rubber boot may do.

I hadn't even thought about that possibility--so now I'm going to watch that boot carefully to see if it does the balloon thing.   

[malik]

OK, so the Breva with its boot at 12 o'clock was never ridden in the wet in its 23,000 km. The shaft on the 65,000 km Nevada was rusted and the splines in a sorry state, and I get water in the swingarms of both the V7s and the V7C (with its new drive shaft) and rust on the shaft. The splines are well greased at each tyre change. During the V7C rebuild I put silicone around the outside of the boot where the snap ring fails to meet. We'll see how that goes, but I don't have a great deal of confidence in it.

What about drilling a hole in the bottom rear of the swingarm under the splines to allow the collected water to drain out?

[sign216]

All this wet weather riding, what, are you in the submarine Corp?

Just joshing you.  I give you credit for braving the elements.

[Chuck in Indiana]

It's hard for me to imagine that it's an issue, unless the design/parts have been changed. Knowing Guzzi, I doubt it.
Here's a picture from the Lario rehab thread.. yes, it fits in a recess, it's pretty tight, and the ring "almost" goes completely around the boot. No, you wouldn't get two rings in there.

[John A]

I dont know about a stone.On my old V700

Completely different animal. Same make though.....

[SmithSwede]

Thanks Chuck.  Interesting photo.  It shows considerably less gap in the fitted snap ring than what is present on my V7 Stone.  I wouldn't expect the Lario boot to leak, whereas the one on my bike definitely does. 

[Zinfan]

I'll just link my experience.  http://wildguzzi.com/forum/index.php?topic=76806.0