Gearbox Drip (case crack)

[LowRyter]

My gearbox has been dripping for a year now.  I thought it was dripping from the drain plug but see it coming from behind the starter.  I assume that I have leak on top of the transmission or there is breather or vent up there. 

 

So I've searched this site as well as the repair manual and can't find the gearbox breather.  Before I take off the tank or perhaps the started motor, I'd like to know what I am looking for and where.  

 

Not a big deal, just a few drops.  Seems to be worse after I ride when the fluid gets warm and a little pressure builds in the tranny.  So the leak doesn't appear to be below the fluid level.

 

A little help guidance here would be appreciated.  I've posted this photo before.  

 

Thanks

 

[Chuck]

So, you've given it the sniff test and know for sure that it is gear oil?

[LowRyter]

yeah, it's the pink stuff in the tranny and it's dripping.  Like the photo.  just a little.  I'd ride it anywhere but it marks its spot. 

[MartyNZ]

Did you read Middle Age Warrior's post? He found a crack in his gearbox casing eventually but many other suggestions there may help you.

http://www.v11lemans.com/forums/index.php?showtopic=19792

 

And here is a picture of the gearbox breather vent on Scud's bike. It is just above midway between the gearbox clutch slave cylinder & output shaft

http://www.v11lemans.com/forums/uploads/post-9991-0-06796100-1487988277.jpg

[Lucky Phil]

Try the shift shaft seal

 

Ciao

[68C]

I had the same leak, although it ran out to the right. An old thread suggested clean the breather, did that, cured the problem.

 

Generally, as Occam's Razor states, the simple solution is normally the right one, more likely to be a blocked vent than a cracked case.

 

Good luck.

[LowRyter]

well, worst case it could be the gearbox is cracked and structurally shot.  The drip has been constant but slight for the last year.  And only occurs after I ride it.

 

Looking at the photos, I still can't locate the vent or the seal mentioned.  To get to it, do I start from the top and tank the tank off or the bottom and remove the started?  Or both?

 

I've looked all these threads and repair manual and still can't make out where to start.

[Scud]

The vent is in front of the swingarm. There's a picture in my recent clutch and shifting problem thread. I don't know if you will need to remove swingarm and subframe to get to the vent. But I had to so I could remove clutch slave. I also posted a pic of the rear trans casting on Lucky Phil's thread about the output shaft seal.

 

Haven't figured out pics. From Tapatalk yet.

 

 

Sent from my iPhone using Tapatalk

[LowRyter]

Thanks Scud.  Now I see the vent.  It's a metal fitting in the top center pointing straight up.

 

But considering the cracked case it's looking much worse then.      I was thinking that if was cracked, it could just be epoxied but since it's on a structural mounting point I might be hosed.  I'd hate to part it out since l love the bike.  

[Scud]

Even though it's green it's worth keeping. :-)

 

I bought a complete low-mile trans recently for less than a rebuild would cost. This is fixable. No more talk of parting that beauty out.

 

 

 

 

Sent from my iPhone using Tapatalk

[LowRyter]

WOW Scud.  I didn't there would be any trannys around.  It's great to know I might have an option if it's worst case.

[Midle Age Warrior]

Hi guys

I had a talk with the welder and he said it is doable and considering my situation I will try this option first, more now that I found a crack in the fork brace of my BMW GS .

LowRyter I am so sorry to hear about your leak because it sound exact like mine, it is no easy to find the source because of the lot of things over the gearbox, my advice is to take the airbox and snorkels off grab a can of carburetor  cleaner a give a deep clean to the area were it meet chassis look at up the pics of thread and I hope you do not find anything like my mines.

[Lucky Phil]

Excellent, lets all launch ourselves to the absolute worst case senario first and forget about that messy basic, simple, methodical, troubleshooting

 

Ciao

[Rolf Halvorsen]

The gear box housing consist of 3 parts.

 

I think Luigi has forgotten to use any liquid seal in the joints when he assembled the gearbox. 

 

I have seen many such gearboxes (first design of the six speed gearboxes from 1999 - 2005) with leaks, and all exept one came from leaking joints. Only one have had cracks in the front part house.

 

Rolf

[thumper]

Years ago I changed the pawl spring, and a small leak developed coming from the through stud on the plate.

On the advice of others here I took a dime and used case sealer to bond it in the hole.

After cleaning the area well. That was 6 years ago all is good.

Look and see where the leak is coming from.