Gearbox output shaft seal

[Lucky Phil]

Just wondering how many miles people generally get out of this seal. I've just changed another one after only around 4000klms and I suspect its had replacments fitted by previous owners. There is no visible issues with the housing, bearing or shaft finish.

I also noticed during my research that the final drive pinion seal and the gearbox input shaft seals are both directional types and oddly the output shaft seal isn't. I have fitted a new non directional type and will see how it goes.

 

Ciao 

[Scud]

I'm replacing one now on a bike with 50,000 miles. While I don't know the history, I'd be surprised if the transmission had ever been removed - so I assume the seal was original. There was not evidence of a leak, but I thought I would replace since I had the cover off to clean out the oil, which had solidified.

 

I replaced the one on my Scura with 12,000 miles. It was fine too - but I replaced preventatively since I was painting the cases.

 

If you're replacing a seal after 4,000 km, then I wonder if something is wrong with the metal surface that mates to the seal. If a seal hardens, it can cut a groove into the metal. Or maybe the new seal had a small cut from start.

 

Interesting on the directional seals. Can you post pics or part number when you get a chance?

[Lucky Phil]

I'm replacing one now on a bike with 50,000 miles. While I don't know the history, I'd be surprised if the transmission had ever been removed - so I assume the seal was original. There was not evidence of a leak, but I thought I would replace since I had the cover off to clean out the oil, which had solidified.

 

I replaced the one on my Scura with 12,000 miles. It was fine too - but I replaced preventatively since I was painting the cases.

 

If you're replacing a seal after 4,000 km, then I wonder if something is wrong with the metal surface that mates to the seal. If a seal hardens, it can cut a groove into the metal. Or maybe the new seal had a small cut from start.

 

Interesting on the directional seals. Can you post pics or part number when you get a chance?

 

This is a front transmission seal, note the directional arrow and the ribs on the seal face orientation for a clockwise (r/h twist) shaft rotation when looking front to rear.

 

This is an anticlockwise (l/h twist seal) note the different orientation of the face ribs. The confusing part in this case is MG cycle are listing this as a V11 rear drive pinion seal which when looking front to rear should be a clockwise directional seal same as the gearbox input seal.Hmmm......

I thought I had sourced a 42x56x7 l/h twist seal for the gearbox output shaft but was mistaken. If anyone knows of one let me know.

 

Ciao 

[Hansson]

I replaced the output shaft seal on my Ballabio -04 preventively when I did work on the gearbox. There was no leakage in the stock seal at 30000 kilometers. Make sure you get a seal with dust lip!

 

HMB Germany, sell the right seal. It's not a directional seal. And I think it's a Viton seal. 

 

http://hmb-guzzi.de/Seal-Ring-gearbox-output-shaft-V11

 

Cheers

[Chuck]

 

If you're replacing a seal after 4,000 km, then I wonder if something is wrong with the metal surface that mates to the seal. If a seal hardens, it can cut a groove into the metal. Or maybe the new seal had a small cut from start.

 

I'm sure Phil has forgotten more about this stuff than I'll never know.. so I doubt that's it. Where's that popcorn emoticon? I'm getting ready to try to learn something..  

Phil, yours is the first one I've heard of leaking.

[Scud]

There is no visible issues with the housing, bearing or shaft finish.

 

 

 

 

If you're replacing a seal after 4,000 km, then I wonder if something is wrong with the metal surface that mates to the seal. If a seal hardens, it can cut a groove into the metal.

 

I'm sure Phil has forgotten more about this stuff than I'll never know.. so I doubt that's it. 

 

...and I just re-read Phil's original post... no issues with metal.

[Lucky Phil]

Here is the HMB Guzzi seal from Hannsons link which they state they only stock the as an OEM part due to quality reasons which is interesting. Is it just me or do i detect faint lines in the sealing face of this seal. Some of these directional seals arnt listed by the OEM as a standard part you can buy but only come as a Ford or GM part etc.

 

Ciao

[MartyNZ]

Two thoughts on that leaky seal.

Is the gearbox vent blocked, forcing oil out the seal as it heats up?

Or was the gearbox overfull? I took out the gearbox sight glass and blasted it clean with brake cleaner so I could see the level clearly. After seeing the photo of Scudd's Champagne gearbox after he took off the selector plate, I don't think I will rely on draining and adding a quantity of oil. http://www.v11lemans.com/forums/index.php?showtopic=19680&page=5&do=findComment&comment=216567

[Scud]

I have one of those seals on order from Harpers - should arrive later this week. Will get a good photo when I have it in hand.

 

The concerns about appropriate quantity of oil may be limited to that thick Redline Heavy Shockproof stuff. After cleaning that mess, I'm going back to the recommended GL-5 gear oil for my transmissions.

[Lucky Phil]

Two thoughts on that leaky seal.

Is the gearbox vent blocked, forcing oil out the seal as it heats up?

Or was the gearbox overfull? I took out the gearbox sight glass and blasted it clean with brake cleaner so I could see the level clearly. After seeing the photo of Scudd's Champagne gearbox after he took off the selector plate, I don't think I will rely on draining and adding a quantity of oil. http://www.v11lemans.com/forums/index.php?showtopic=19680&page=5&do=findComment&comment=216567

Yes good points, I did check the venting and it was fine, the level was to the middle of the sight glass which really should be fine but I have dropped it to the bottom to cover the level issue off. I've been using the Redline heavy oil just recently just for comparison purposes ( shifts about the same as any other oil for mine) and it does have the advantage of color which is really useful when it comes to sourcing the leak.

After the test ride post seal change the gearbox area looked fine but I noticed oil on the pork chop plate the brake lever and my right boot, odd I thought esp since it was a golden color. Then I noticed the rather significant r/h rocker cover gasket leak.....doh. Talk about target fixation on the gearbox leak, I just have to re learn things as I get older it seems.

It appears these directional seals tend to be mainly used in areas that are difficult/expensive to replace for some added insurance over leaking. Most automotive front and rear crankshaft seals and gearbox input shaft etc. The Big Block guzzies also on the back of the crank.  

 

Ciao 

[Lucky Phil]

I have one of those seals on order from Harpers - should arrive later this week. Will get a good photo when I have it in hand.

 

The concerns about appropriate quantity of oil may be limited to that thick Redline Heavy Shockproof stuff. After cleaning that mess, I'm going back to the recommended GL-5 gear oil for my transmissions.

Very good, I'll be interested to see what the OEM seal looks like. Yes the Redline sludge photo surprised me although I dont know the storage details but strange none the less.

 

Ciao  

[Scud]

That bike sat for about three years in Indiana, which has some bitter cold winters.

 

Here's the seal I removed from it. The inner part has a wave pattern with 5 crests to complete the circle. You can see two of the crests in the photo.

 

[docc]

Glad to be learning all about these special seals . . . but even better to see that Scud's wifey's white shag carpet is holding up so well to all this V11 refitting.   

[footgoose]

That bike sat for about three years in Indiana, which has some bitter cold winters.

 

Here's the seal I removed from it. The inner part has a wave pattern with 5 crests to complete the circle. You can see two of the crests in the photo.

 

IMG_5801.jpg

 

 

I was going to mention but questioned my own vision... Lucky Phils photo of the seal with "faint lines" looked to me as going in both directions, IE - wave.

[Lucky Phil]

That bike sat for about three years in Indiana, which has some bitter cold winters.

 

Here's the seal I removed from it. The inner part has a wave pattern with 5 crests to complete the circle. You can see two of the crests in the photo.

 

IMG_5801.jpg

AhHa....excellent work scud......This is another variation. Although the plain faced seals are supposed to be bi directional I have also seen drawings and tech info on ribbed face seals that allow for rotation in either direction with the pattern in a W layout accross the face but this wave style is new to me.

So we have seals with straight angled ribs on them orientated in directions to suit either CW or CCW rotation, seal faces without ribs for either CW or CCW rotation and the wave rib ( as pictured) for CW or CCW rotation and the W  type ribs for CW or CCW.

I still think that the directional RIBBED style seals be they CW,CCW or BI directional must be for extra insurance agains leakage and/or for locations that would require significant disassembly to replace, hence the use on crankshaft and gearbox seals.

Will be really interested to see what the OEM replacements look like if you can share a photo scud.

The seal I replaced on my bike 4000klms ago certainly didnt have any ribs or wave pattern so looks like it had been replaced already and I assumed it was just a plain std seal. I was talking the Brad Black ( Brad the bike boy, well known very good Italian bike mechanic here in Melbourne ) at the track the other day and he said he always just uses the OEM seals for replacement as the cost is low and there are no hassles. Looks like good advice. 

 

Ciao