Oil Leak

Discussion in 'Old's Cool' started by tigerapple, Dec 26, 2006.

  1. tigerapple

    tigerapple Adventurer

    Joined:
    Dec 24, 2006
    Oddometer:
    69
    Location:
    Singapore
    Hi..I have been having some oil leak from the left hand rubber intake tube (see pics). It seem to be coming out from the intake tube onto the carb before dripping onto the gear shift lever. As a result, the gear shift lever gets all oily and i am having a constant oil patch on my boots. After removing the intake tube I was told that this has possibly have to do with a dirty airbox, air filter resulting in excessive oil flowing out from the breather tube inside the rubber intake tube. The seals on the gear shift lever has been changed and other checks confirmed that oil could not be flowing from other parts. Im really not sure how this works so i am posting here to hear comments from anyone who might have this problem before and would be most pleased to hear some solutions as well. Btw, this is on a 1988 R100GS PD..

    Thanks for taking the time to reaad this... :wink:

    Attached Files:

    #1
  2. tigerapple

    tigerapple Adventurer

    Joined:
    Dec 24, 2006
    Oddometer:
    69
    Location:
    Singapore
    Oil seems to be leaking from the joints of the intake tube on the side nearer to the carb..

    Attached Files:

    #2
  3. tigerapple

    tigerapple Adventurer

    Joined:
    Dec 24, 2006
    Oddometer:
    69
    Location:
    Singapore
    Another pic showing oily gear shift lever..

    Attached Files:

    #3
  4. jtwind

    jtwind Wisconsin Airhead

    Joined:
    Nov 19, 2004
    Oddometer:
    3,484
    Location:
    Madison WI
    Usually oil in the airfilter is from a bad crankcase breather. It's under the starter cover next to the starter on the brake lever side. I've yet to see one put out that much oil but it's possible and where I would start looking. JT
    #4
  5. El Hombre

    El Hombre Banned

    Joined:
    Jul 19, 2006
    Oddometer:
    1,536
    Location:
    Alta Coma, California
    That's not an oil leak; it's just sweating horsepower!
    #5
  6. hogmolly

    hogmolly Dude

    Joined:
    May 28, 2003
    Oddometer:
    3,144
    Location:
    McKinney, TX and San Jose, CA
    I would check for other possible sources just to be sure. Maybe a pushrod tube wicking oil back towards the intake, things like that. If it is your crankcase breather, pulling the carb should show you lots of oil. An intake that's air tight is usually oil tight as well.
    #6
  7. jtwind

    jtwind Wisconsin Airhead

    Joined:
    Nov 19, 2004
    Oddometer:
    3,484
    Location:
    Madison WI
    hogmolly may be right, easy to find out. There are lots of things on that shifter side that can leak, base of the cylinder, two pushrod seals, the oil pressure sender, shifter seal and maybe even the oil pan gasket. Along with the oil breather there are plenty of things to check. You can check the oil breather easily as mentioned, take a carb rubber off or look at the air cleaner. Otherwise I'd clean all the other spots up really, really well and then keep an eye on them. JT
    #7
  8. Crush

    Crush Been here awhile

    Joined:
    Oct 20, 2003
    Oddometer:
    994
    Location:
    Anchorage, AK
    I've got a similar looking oil leak. Mine is from the pushrod tube where it is pressed in the head. I'm thinking of trying some wicking locktite to seal it.

    Good luck, Dennis
    #8
  9. camgregus

    camgregus riding gently now

    Joined:
    Feb 24, 2006
    Oddometer:
    3,014
    Location:
    on the banks of the mighty mississippi, AR side
    wicking locktite?
    #9
  10. storymitchell

    storymitchell Member of the proletariat

    Joined:
    Jun 10, 2003
    Oddometer:
    1,268
    Location:
    The autumn of my discontent (Hillsboro, VA)
    Chances are you need to replace the pushrod tube seals: http://www.gunsmoke.com/motorcycling/r100gs/pushrod_tubes/index.html

    I don't have a picture, but perhaps someone on the list can post a pic of a homemade pushrod tube seal repair tool? Basically it's a pipe with an ID slightly larger than the OD of the pushrod tube with 180 degrees cut off and a small angle cut on the end. You can put it over the seal and give it a wack or two with a mallet and many times this will stop a minor leak.
    #10
  11. GSPD750

    GSPD750 Adventurer

    Joined:
    Feb 14, 2005
    Oddometer:
    1,474
    Location:
    Calgary, AB
    Sure it's not fuel dripping onto the rubber from the carb and TURNING it into oil. ??
    #11
  12. jtwind

    jtwind Wisconsin Airhead

    Joined:
    Nov 19, 2004
    Oddometer:
    3,484
    Location:
    Madison WI
    This isn't always a good idea and only a short term fix in any case. The later airheads have the pushrod seal collar brazed on. If you tap it in, it may move but you are actually pulling the pushrod tube out of the head. If you've ever installed a pushrod tube and tried getting it to the correct depth you'd know this wasn't a good idea. These seals start to leak because the rubber gets old, loses it's flexibility and doesn't respond to the expansion and contraction of the cylinder and heads very well. When they leak they need to replaced. JT
    #12
  13. camgregus

    camgregus riding gently now

    Joined:
    Feb 24, 2006
    Oddometer:
    3,014
    Location:
    on the banks of the mighty mississippi, AR side
    there are some good pushrod replacement links...
    #13
  14. Crush

    Crush Been here awhile

    Joined:
    Oct 20, 2003
    Oddometer:
    994
    Location:
    Anchorage, AK
    Yep, Loctite 290 wicking grade p/n 29021.

    The leak on my engine is definitely from the pushrod tube where it is in the head, not from the seals on the block.

    Cheers, Dennis
    #14
  15. Kewaneh

    Kewaneh Where am I?

    Joined:
    Mar 21, 2006
    Oddometer:
    46
    Location:
    Kerman, California
    I'm having a similar problem with my 93 R100GS, but it's on the right side. I'm getting oil on my rear brake lever and down the right side of the oil pan. I suspected the pushrod tubes. The bike has always dripped a bit since I've had it (a drop or two every week or so) but it recently turned into a Brit-bike mess. I cleaned everything off a few weeks ago, warmed it up and let it sit. It wasn't long before I could see the oil on the side of the oil pan, just below the pushrods.

    [​IMG]

    [​IMG]

    I was really concerned when the I couldn't figure out where the oil was coming from. It was everywhere on the right side and impossible to pinpoint the source until I cleaned it (although the pushrods were the original suspect). After a ride, I noticed that the toe of my right boot was splattered with oil and I realized that during a ride, the oil gets caught in the blow-by wind and sprayed on everything. And it doesn't take much oil to make a huge mess. I would suspect that a leak at the left pushrods would spray oil on the shift lever, and elsewhere on the left side, as well.

    [​IMG]

    A mechanic I spoke with suggested tapping the seals back in with a half-round pipe and a mallet too. He also suggested great care in the process. The other suggestion was just replacing the seals altogether. That's probably the route I'll go. Not quite what I had in mind with my bonus this year.

    - Kewaneh
    #15
  16. Mugwest

    Mugwest .

    Joined:
    Oct 18, 2005
    Oddometer:
    7,593
    Location:
    3rd Ring of Buzztopia
    just for a been-there-done-something-similar data point: make sure you don't have a failing headgasket that lets oil weep out and spray yr boot. Had i not experienced this on my G/S's orig 800 motor i would'nt have believed it was possible: this motor had an upper cyl stud backing out of the case which made fully torquing the head impossible. With the head torque uneven the head gasket started weeping oil, but not enough to compromise compression, go figure. The cylinder in question (right side) weeped oil vigorously from the top edge of the cyl/head interface, such that slipstream air put an oil stain on the right leg of all my jeans and riding pants.
    Again, i would have expected compression loss but it never happened-- the oil leak just got more severe until i swapped motors.

    seals on the pushrods or a failed breather are statistically more likely (in that order), but check yr head gasket area while you're eyeballing. The quick clue-in is oil from the head/cylinder joint fins that is confirmed not coming from the valve cover.
    #16
  17. jtwind

    jtwind Wisconsin Airhead

    Joined:
    Nov 19, 2004
    Oddometer:
    3,484
    Location:
    Madison WI
    Pushrod seal replacement is not the big bugaboo it's made out to be. About $50 in parts and 2-4 hours of time. JT
    #17
  18. tigerapple

    tigerapple Adventurer

    Joined:
    Dec 24, 2006
    Oddometer:
    69
    Location:
    Singapore
    Thanks for the comments; really appreciate it.

    Well, i did take out the intake tube and saw oil coming out from the breather tube. So if a failed breather tube is the problem and oil is coming out from it; how do i deal with it? Change the tube? Or is there something else i need to manage?

    The push rod tube seals is also a goner. This is obvious in my case because i can see clearly the pieces of the seals already falling off due to wear and tear. Just that in this case after i removed the intake tube and tracing the flow of the oil, it does seem that oil from the breather tube is a higher possibility.

    So any suggestions as to how i can manage this? Should i remove airbox, clean it up together with my air filter (KNN) Change to new intake tube for better sealing at the edges? What else should i be doing?

    Just some of thoughts here. Thanks.
    #18
  19. Middleweightboxer

    Middleweightboxer Middleweightboxer

    Joined:
    Feb 10, 2005
    Oddometer:
    682
    Location:
    Paradise, TX
    Try turning the hose clamp around where the screw is on top. That should eliminate the breather oil leak (for a while).
    #19
  20. Solo Lobo

    Solo Lobo airhead or nothing

    Joined:
    Mar 16, 2004
    Oddometer:
    9,230
    Location:
    Shoreline, WA
    It may not be a failed breather, but blow-by caused by worn rings/valves... do a search for breather and see a thread I started... I by-passed the stock breather system and put together a new one that aviods the carb-fouling original OEM design...

    Oh, toss the K&N filter.... do a search to find out why.... especially if you ride your GS off-road.

    #20