This can't be good.

Discussion in 'GS Boxers' started by bemiiten, Nov 26, 2006.

  1. Mr. Magoo

    Mr. Magoo TeeMarrZee

    Joined:
    Oct 10, 2006
    Oddometer:
    5,059
    I would like to have your wrenching skills. Good luck! :clap
    #21
  2. Komet

    Komet The Voice of Reason

    Joined:
    Feb 2, 2002
    Oddometer:
    38,096
    Location:
    Memphis, Tennessee
    Concur.:clap
    #22
  3. kdude

    kdude Happy to be here !

    Joined:
    Feb 19, 2004
    Oddometer:
    2,029
    Location:
    Surfside, Florida
    Oh Man.. What an exciting post ! Can't wait to see how it all turns out. good luck.
    #23
  4. dannyleo

    dannyleo Been here awhile

    Joined:
    Aug 23, 2003
    Oddometer:
    301
    Just a guess, input shaft bearing. Had exactly the same type of description as what you gave and that's what they found on pulling it apart. It felt just a shade unsmooth until you pushed on it at the same time as turning it, then it was downright gritty. Be interesting to hear how it turns out.
    #24
  5. bemiiten

    bemiiten League of Adventures

    Joined:
    Jul 10, 2003
    Oddometer:
    5,179
    Location:
    Hamilton NJ.
    Here is a pic of the metallic fuzz on the black magnetic drain plug found at the bottom of the transmission. When I discovered the problem , first thing I did was to remove the fill plug to inspect the oil level. It was fine. Next I drained the gear oil into a clean pan to check for debris with a magnet. There was a little bit , but the small amount of fine metal particles in the hot oil would give me little concern normally.
    I never removed the black magnetic drain plug on the bottom of the trans before because the cat. needed to come off to gain access. I found a short 3/8 bolt that has a 9/16 hex fit's perfectly. I put on two nuts and used a wrench to remove the plug with the exhaust in place.​
    I would soon find out that despite the service manual making no reference to remove and clean this plug for normal maintenance, not doing so was a major blunder on my part. :baldy The plug was absolutely filled with super fine metallic fuzz. I cleaned it up , refilled the trans and decided to take the bike for one last ride around the block to listen to the grinding noise one more time and to shoot the video. I should mention I drained the final drive just to make sure That the noise wasn't being transmitted somehow to the trans. Nothing at all was found on the drain plug.​
    Here is a picture after I cleaned the trans plug once already. I rode the bike less than a mile and managed to pic up this much more debris!!! :eek1 ​
    [​IMG]
    You can bet that this will be coming out at every service from now on!​
    #25
  6. bemiiten

    bemiiten League of Adventures

    Joined:
    Jul 10, 2003
    Oddometer:
    5,179
    Location:
    Hamilton NJ.
    This is what was recommended by the dealer. I normally use what is called for in the manual. I already was using the 75/140 before I discovered the fact that it calls for 90w. This issue has been debated here before.​
    [​IMG]
    Over the years , The container has been changed but what came out looked the same. BMW's latest lubricant is now red in color where the old stuff was the normal gold/brown color.​
    Being the anal type, this set off alarm bells at my last fluid change. 5,000 miles later , bearing failure. :huh
    So I'm left wandering why shit happens. So what do you think?​
      • The fuzz in the oil found it's way into the bearing and destroyed it.
      • The large amount of fuzz is from the bearing failure
      • The bearing was improperly shimmed at the factory, but took 55k to fail.
      • The catalytic converter's excess heat played a role in cooking the bearings.
      • Changing to the red oil did it!!!
      • The case is improperly machined , hence the reason the bearing would not come out while all the rest were falling out at a much lower temp.
      • Shit happens
    #26
  7. JimVonBaden

    JimVonBaden "Cool" Aid!

    Joined:
    Feb 11, 2005
    Oddometer:
    61,827
    Location:
    Alexandria, VA
    Just a few of my opinions:

    The fuzz isn't a concern unless it had very descernable chunks, or flakes of metal on it. Notmal wear and tear, along with break-in will create very small fuzzy particles that nicely stick to the magnetic pick-up.

    The different color of your oils mean nothing. They have different colors so I wouldn't worry about that.

    I would bet that it was just your time. It seems like you did all the correct maintenance, so I wouldn't blame yourself.

    Jim :brow
    #27
  8. blackbirdzach

    blackbirdzach Daily Adventurer

    Joined:
    Jun 9, 2006
    Oddometer:
    3,430
    Location:
    15 mintues West of Atlanta
    I'm very impressed. I wish I had the tools and knowledge to work on my own stuff.
    #28
  9. SQD8R

    SQD8R Eat squids and be merry

    Joined:
    Jun 16, 2004
    Oddometer:
    7,421
    Location:
    The Village: 75°53'34"W, 45°17'42"N
    Hey Bemiiten,

    Nothing to add other than appreciation for the time you are taking to show us your progress. :thumb

    Dale
    #29
  10. bacon

    bacon KZ5TLP

    Joined:
    May 14, 2004
    Oddometer:
    615
    Location:
    Mississippi
    Hey Bemiiten

    When you made the vary first post I almost spoke up to tell you what I thought it might be. Well I have been following this and I am so glad I did not say anything to show how stupid I am. You are so far advanced in your ability I don't have a chance. If I get my valves set and TB's set I think I did some thing. Well thanks for taking your time and making us all feel so small.
    Thanks for a great thread:clap
    Tim
    #30
  11. johnjen

    johnjen I've Been Resigned

    Joined:
    Nov 28, 2001
    Oddometer:
    16,545
    Location:
    Seattle
    This is great stuff... It would be a fine addition to the HoW if Be-sMiiten is agreeable.

    JJ
    #31
  12. Gonz

    Gonz BMW Bike Bum

    Joined:
    May 4, 2002
    Oddometer:
    756
    Location:
    Dubbo NSW
    Neat post, thanks heaps for taking the time to share!!!
    #32
  13. BlkAtak

    BlkAtak BlkAtak

    Joined:
    Oct 18, 2006
    Oddometer:
    12
    Location:
    Central California,,, Ahhhhh
    my cousin had his tranny go out completely on his bike and had it replaced. dealer said its a common flaw... he got it replaced and got a year warranty on the new one. he'll be getting rid of the bike with the warranty is up and getting something new. sorry
    #33
  14. Jim Bud

    Jim Bud Long timer

    Joined:
    Apr 25, 2003
    Oddometer:
    3,439
    Location:
    Sedalia, CO
    the rest of the trans looks to be in pretty good shape.....

    its possible your box started out life with a problematic bearing??

    shame, but always possible....

    I think I will check my magnetic plug next time....dropping the exhaust system is not all that hard.....it will give me a reason to take off the center stand and give it a complete lube/rebuild.....

    Thanks for the complete description....
    #34
  15. bemiiten

    bemiiten League of Adventures

    Joined:
    Jul 10, 2003
    Oddometer:
    5,179
    Location:
    Hamilton NJ.
    Sounds good! But were not in the clear yet. If I screw up ,it could turn out to be the HoW NoT to do it :eek1 This is only my second transmission job and my first on a beemer , so I am no expert by any stretch. ​
    I spent some time thinking if I should take the transmission shafts to a dealer and have them swap the bearings. After careful consideration, I ordered a shop press and a bearing separator kit. :wink: Also in the works will be a way to drive the seals home properly, penny tech style.​
    I will post a update when the parts & tools arrive.
    #35
  16. johnjen

    johnjen I've Been Resigned

    Joined:
    Nov 28, 2001
    Oddometer:
    16,545
    Location:
    Seattle
    I've been involved with several tranny rebuilds. They were all on airheads but the basics are the same. That isn't to say there won't be specific differences... One, if not the most signifigent aspect of tranny rebuilding is getting the shimming done properly. We developed a method where we dialed in a tranny and the differences are amazing. Most won't/don't want to go to the trouble/time spent to get this one aspect 'just right' but when you do the tranny shifts like a japanese gear box. Well actually like a german box with the snick-snickability of the japanese xmissions.

    I can wait till the project is 'done' before we immoralize it for all posterity:lol3

    JJ :wink:


    #36
  17. rideLD

    rideLD The further the better!

    Joined:
    Jul 15, 2004
    Oddometer:
    5,412
    Location:
    Omaha, Nebraska


    You are also very modest. You are demonstrating tremendous mechanical aptitude.:clap

    This is my first BMW and I have never had the rear end off it. If it is ever necessary, I will do it. What little I know I about working on bikes I have learned by getting myself in over my head.:lol3

    That's the right attitude. You've been successful in disassembly and diagnosing the problem might as well see it through to the conclusion yourself. You have already saved close to a thousand dollars in labor. Whats a couple hundred in tools.:lol3 Here's to your successful conclusion.:beer
    #37
  18. bemiiten

    bemiiten League of Adventures

    Joined:
    Jul 10, 2003
    Oddometer:
    5,179
    Location:
    Hamilton NJ.
    My plan for shimming consists of carefully measuring the assembled length of the existing shafts. After the bearings are removed , I will compare them to the new ones as well. This should hopefully result in me being abel to match the same size that came out.​
    One big assumption here is that they were shimmed properly to begin with! ​
    This is uncharted territory for me so any knowledge or suggestions would be greatly appreciated.​
    Thanks to all for your encouragement and kind comments. ​
    #38
  19. hogmolly

    hogmolly Dude

    Joined:
    May 28, 2003
    Oddometer:
    3,144
    Location:
    McKinney, TX and San Jose, CA
    Plastic gauge is what I used on an airhead transmission. Don't forget to include the gasket thickness (or use a gasket when you measure).
    #39
  20. slideways

    slideways permanent ex-pat

    Joined:
    Mar 1, 2003
    Oddometer:
    6,844
    Location:
    The Bahamas Mon.
    I have not rebuilt any BMW transmissions but have done a few Japanese transmissions.

    The main difference I see is that the bearings are pressed on the the shafts and interference fit into the cases.

    When installing new bearings into the cases I always put the bearings in the freezor over night and usually they just drop into the cases.

    For installing the bearings on the trasmission shaft I would put the entire assy in the freezor over night. Then find a socket that matches the inner race on the bearing and heat it red hot on the stove. put the hot socket on the inner race for a minute then pull the shaft assy out of the freezor and the bearing should slide right on.

    If you need to extract any blind side bearings from the trasmission cases Snap-On makes a blind side bearing puller.
    #40