Leaking final drive or tranny with few clues

[Crazy Noodle]

Hi,

 

Final Drive boot is weeping and dripping on to the rear rim and tire when parked. a couple of drips per night.

 

I pulled back the boot, could not "see" the oil. Residue would be on finger when I felt around. Seemed like I got more of the top metal piece (final drive) which I thought indicates the final drive is leaking? Seems like oul could not get on this suspended piece if it was leaking from the tranny?

 

I then opened up the final drive filler cap and 90 weight came pouring out Wonder if it was overfilled when I filled it up last year in the cold weather? Could this have created a situation where it was pressurizing the final drive forcing oil to leak out? Looks like it has a breather on top but I am unsure. I did remove some oil just in case.

 

I am going on a long trip next Wednesday and I am a bit concerned. Any ideas? How hard is it to replace the real seal? Can you just do the seal or do you need to pull out bearings?

 

Anyone with experience with this type of situation and what should be done?

 

Thanks,

 

Todd

[AndyS]

I think you will find many, many, of us have a seeping rear seal. Mine has been like it for 2 years, and it is of nuisance value as it makes the bike washing sponge dirty, however I have never noticed an appreciable drop in fluid levels and I would suspect that unless it really is pouring out and causing a safety issue with rear tyre or brake pads it is something to be done at your convenience. Even if the level dropped to below the level of the input shaft I am sure you would have enough splash and dipped lubrication.

Andy

[T__]

Hi,

 

Final Drive boot is weeping and dripping on to the rear rim and tire when parked. a couple of drips per night.

 

I pulled back the boot, could not "see" the oil. Residue would be on finger when I felt around. Seemed like I got more of the top metal piece (final drive) which I thought indicates the final drive is leaking? Seems like oul could not get on this suspended piece if it was leaking from the tranny?

 

I then opened up the final drive filler cap and 90 weight came pouring out Wonder if it was overfilled when I filled it up last year in the cold weather? Could this have created a situation where it was pressurizing the final drive forcing oil to leak out? Looks like it has a breather on top but I am unsure. I did remove some oil just in case.

 

I am going on a long trip next Wednesday and I am a bit concerned. Any ideas? How hard is it to replace the real seal? Can you just do the seal or do you need to pull out bearings?

 

Anyone with experience with this type of situation and what should be done?

 

Thanks,

 

Todd

 

Todd, try draining the final drive then installing the correct amount of gear oil.. Overfilling (by more than slightly) it will usually puke oil out the vent but shouldn’t significantly increase seal leakage.. Maybe try a different brand of gear oil,, some oil types/brands seem to leak past older seals more than others.. My old GoldWing seems to leak more when using Mobil 1 synthetic gear oil & seems to be almost dry when using plain old 80W90 Dino gear oil (probably more seal conditioner in the old style Dino gear oil)..

 

Twisty

[Ken H.]

Can you post a photo of the leakage?

[Crazy Noodle]

Hi Ken,

I cleaned it all up last night. Unfortunately, it looks really good right now. Is this a common problem? I am using Amsoil 90 wgt currently. It did not leak when I first went to this at 20k. I currently have 34k.

 

Thanks,

Todd

[Ken H.]

Is this a common problem?

Slight seepage from the input shaft seal under the boot is a bit common, oozing out the vent on top from an over fill or certain brands of lube foaming (Redline in particular) is common, beyond that, other leaks - no.