Oil coming out the crankcase vent

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by skidxr, Jan 6, 2014.

  1. skidxr

    skidxr Excuses

    Joined:
    Mar 7, 2006
    Oddometer:
    432
    Location:
    Durango, Colorado
    Hi all.. On my 990 Adv I had a lot of oil coming out of the crankcase vent. Enough that it left a puddle under the bike. I had just returned from a trip where I was cruising for hours at or above 5K RPM. I was wondering it that could be the reason or do I have other problems? I have the CPR filter without the hose that directs the vent into the rear TB. I could not get the filter on with the hose in place. So it just shot in the filter and ran all over the place. New fresh looking oil not goo. I didn't over fill the oil tank either. Had I run the hose into the TB it would have taken a big dose of oil. I rode 1000 miles one way and 1000 miles back and it didn't show up or I didn't notice it until I got home.
    #1
  2. BigTony

    BigTony Been here awhile

    Joined:
    Apr 4, 2011
    Oddometer:
    254
    Same problem here... I think it was doing it before I put the new air filter on the bike because the foam ring on the air filter that goes around the TB had oil soaked in when I pulled it off. But now that I've got the new air filter I see the magnitude of it. I've got a simple breather filter on the hose and it made a big old mess on a couple day ride I just did.

    Based on some searching here on the forum, it seems the first thing to check is the balancer shaft seal under the generator cover (cheap). If not that, then it's likely a ring seal problem (engine overhaul - ouch). (There are part numbers in the 950 how under known problems)

    I'm curious for anyone who's replaced the balancer shaft seal how they got the old seal off...
    #2
  3. DirtyADV

    DirtyADV Long timer

    Joined:
    Jan 13, 2007
    Oddometer:
    2,864
    Location:
    SWEDEN, Skellefteå
    Screwdriver:

    [​IMG]


    Did it just before heading for Russia last summer and the catchbottle I had rerouted the hose to got a leak so could not get a good before and after comparison.

    http://www.dirtyadv.com/balancer-shaft-seal-replacement/

    /Johan
    #3
  4. skidxr

    skidxr Excuses

    Joined:
    Mar 7, 2006
    Oddometer:
    432
    Location:
    Durango, Colorado
    I hope that seal is the issue. I just picked one up today but had to order the gasket. I'll report back on the outcome in a week or so.

    Thank you guys !!!
    #4
  5. skidxr

    skidxr Excuses

    Joined:
    Mar 7, 2006
    Oddometer:
    432
    Location:
    Durango, Colorado
    Man I hope so !!!
    #5
  6. BigTony

    BigTony Been here awhile

    Joined:
    Apr 4, 2011
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    254
    Awesome write up Johan!!! This is extremely helpful - a link to that post should be added to the HOW
    #6
  7. DirtyADV

    DirtyADV Long timer

    Joined:
    Jan 13, 2007
    Oddometer:
    2,864
    Location:
    SWEDEN, Skellefteå
    Have done a small update to that post, this is what the content of the catch bottle looked like after it had sat for a while:

    [​IMG]

    And the gasket for the cover can be reused, had it off several times before so replaced that time even if it probably wasn´t needed.

    /Johan
    #7
  8. skidxr

    skidxr Excuses

    Joined:
    Mar 7, 2006
    Oddometer:
    432
    Location:
    Durango, Colorado
    Just an update. I did about 2000 miles on a trip and no more oil is coming out of the crankcase vent..

    Once again y'all here saved the day !!

    Thank you !!!
    #8