Crank Seal Installation
  • Flipg123
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    Joined:Tue Nov 04, 2014 3:44 pm
    Crank Seal Installation

    by Flipg123 » Tue Sep 29, 2015 4:58 pm

    I am replacing the crank seals in a 2004 250r and I'm wondering how deep in the case the seal should go on the clutch side of the crank. I am assuming that it should push in far enough to touch the crank bearing, otherwise there will be a leak there, but want to make sure.
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    JimDirt
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    by JimDirt » Tue Sep 29, 2015 5:55 pm

    You install the seal so it is flush with the case (not recessed to the bottom) , the flat side goes out for 2004 -05 , after 2005 the seal goes in facing backwards , but still the edge is flush with the case , not recessed
    2020 CRF450R
    2006 CRF450X
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    Weiser , Idaho
  • Flipg123
    Posts:4
    Joined:Tue Nov 04, 2014 3:44 pm

    by Flipg123 » Wed Sep 30, 2015 6:49 am

    So how is the seal between the clutch case, and the crank case completed? When I put the seal in flush with the case, there is a gap between the outside crank bearing and the seal. I suppose that the gear that slides on the crank could sit tight to the seal and make things air tight.

    I am asking because I was getting oil from the shifter side of the engine to the brake side of the engine and suspect leaky seals. I have it tore apart for the second time and just want to be sure that it is done right this time.

    I was also getting coolant in both sides, but that is another post.

    BTW I have probably put about 4 hours on the bike since I replaced the crank, so the seals were new, but I think that they were installed incorrectly.
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    JimDirt
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    by JimDirt » Wed Sep 30, 2015 7:18 am

    This is directly from the Factory Honda Service Manual for your bike , and yes the seal rests against the gear
    Image

    The oil can transfer a few ways , from a clogged vent building up case pressure , to a failed seal , to the gasket between the 2 case halves , to the one way flapper valve on the ignition side of the case , coolant in both sides is a head or base gasket or a defective/damaged cylinder , or a water pump seal , did you also replace the Balancer Shaft Seal ?? , the right seal usually allows oil to go from the tranny side TO the engine side , not the other way , going from engine to tranny is most likely one of the things i mentioned above , i am guessing the Balancer Shaft Seal
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • Flipg123
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    Joined:Tue Nov 04, 2014 3:44 pm

    by Flipg123 » Thu Oct 01, 2015 9:10 am

    I haven't replaced the balancer shaft seal, but think that I will. It is much easier to do it now, that it is apart rather than tear it down again if it is still leaking.

    I think that the antifreeze is my water pump seals. I noticed antifreeze coming out of the weeping hole which I believe would indicate that it is passing through the first seal.
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    JimDirt
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    by JimDirt » Thu Oct 01, 2015 1:08 pm

    Yea it sounds like that is the water pump seal if its weeping
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho

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