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Mark 3 crankshaft seal retainer

Discussion in 'Norton Commando Motorcycles (Classic)' started by sadolfsonmark3, Nov 28, 2019.

  1. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    I am rebuilding my 1975 mark 3 have the primary off and apart and am looking to replace the drivers side crankshaft oil seal. there is a wire retaining clip holding the seal in place. It is not a normal retaining ring and I can't find anywhere to grab it and get it out of the slot. I seem to remember that many years ago I did get it out but I don't recall how. Does anyone have a method of getting it out of there without marring up the whole situation?
     
  2. Ron L

    Ron L VIP MEMBER

    Joined:
    Feb 27, 2004
    The circlip should have a bent end that you grab with a small plier or pry out with a small screwdriver blade. If there is no bent end you should be able to use a sharp pick under the end.
     

    Attached Files:

  3. Madnorton

    Madnorton

    Joined:
    Jun 9, 2008
    Use some old 8 thou feeler gauges to get a lift on it and then snipe knose pliers.
     
  4. Classic Cycle Repair

    Classic Cycle Repair

    Joined:
    Apr 1, 2019
    Yes, use a razor blade. It lifts very easily.
     
  5. The Buckeye Rider

    The Buckeye Rider

    Joined:
    Jan 1, 2005
    I have used a dental pick with good results.
     
  6. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    Unfortunately mine doesn't look at all like what's pictured above. Instead it is just a flat coil that sits in the groove with no way to grab it. I'd load a picture but I doubt it will show well. I'll still try to get behind the edge and see if I can pull it out. I may have to get a dental pick! Thanks for the replies.
     
  7. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
  8. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    The old seal doesn't look in too bad shape so I think I'll just leave the old seal in and smear some RTV high temp sealant around the edge. I also have a reed type crankcase breather on the way and that will help stop the oil migrating into the primary.
     
  9. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
  10. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    Why they didn't just use a normal circle is a mystery??
     
  11. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    circlip.
     
  12. Torontonian

    Torontonian

    Joined:
    Dec 28, 2009
    If you had engine oil migrating through the seal and into the primary then you must change that seal. I change it as a matter of course each time the primary comes apart , matter of course. Same goes for earlier models.
     
  13. Ron L

    Ron L VIP MEMBER

    Joined:
    Feb 27, 2004
    Interestingly enough, the parts book diagram actually shows this as a standard circlip!
     
  14. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    As background the bike sat for a few years and the oil drained into the bottom of the crankcase. Many years ago I had used heliacoils on the two bottom studs holding on the outrigger plate and used loctite on the studs but the over the years I think that may have been a source of oil seepage. I have the metal rimmed seal and I have read elsewhere on this forum that the oil can seep around the outside of it. I'd like to replace the seal with the rubber rimmed one but as I stated I cannot get the circlip out. Perhaps if I drilled into the old seal and forced it out of there I MIGHT be able to remove the ridiculouss circlip but if I can't I will have no seal and a useless motorcycle. At this point I think I will leave the oil out over the winter and when I get it running (hopefully) in the spring I will check for seepage by removing the primary drain plug every few days and drain what little oil is in the primary out. I'd also like to do something to stop any wet sumping eventually. but that is a whole 'other subject.
     
  15. maylar

    maylar VIP MEMBER

    Joined:
    May 13, 2007
    I think if I were in your position I'd do whatever was necessary to resolve the issue and get that clip out. There must be a way.

    Can you show us a picture?
     
  16. Fanfan26

    Fanfan26

    Joined:
    Mar 14, 2012
  17. Torontonian

    Torontonian

    Joined:
    Dec 28, 2009
    It shouldn't be that hard to do. Get something under the clip. Like a jeweler's tool , a very small screwdriver , a pick tool or whatever and prise it over the lip. Then grab it with fine needle nose pliers and don't sweat about being brutal with it as you will be replacing it and the seal itself.
     
  18. maylar

    maylar VIP MEMBER

    Joined:
    May 13, 2007
    I wish the older cases had a retainer. I went to change the seal on my 74 and it literally fell out in my hand. New one went in with some Yamabond around it.
     
  19. sadolfsonmark3

    sadolfsonmark3

    Joined:
    Jan 5, 2012
    I wish it had a retainer like the one pictured above and it would be simple to get out. Mine is flat like #14 in the Oldbritts Group 5 parts but it' s continuous ring and there are no holes for a snap ring pliers. My seal doesn't look too bad and The inner
    hasn't been pushed out.. I have Hondabond. Might be better than RTV. I'll let it sit a while and work on my other bike seeing's how there is a foot of snow on the ground and maybe I'll have a brainstorm. And try to post a pic that will capture what I'm talking about. Thanks for your responses guys!
     
  20. Torontonian

    Torontonian

    Joined:
    Dec 28, 2009
    How old is the seal and/or how many miles on it ?
    A seal is cheap and you are in there already.
     

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