Crankcase O-rings

4 replies to this topic
  • finthat

Posted April 11, 2009 - 08:21 AM


I did the old "I'll remeber where that goes" and forgot which crankcase dowels get an O-ring. If you have the parts diagram I can figure out where #21 and 20 go but I have another dowel with an O ring on it and can't find it in any diagrams. I know I left the O ring the dowel to at least be sure that it had one when I went for re-assembly. I should no better by now I'm a big boy now!! :p

  • grayracer513

Posted April 11, 2009 - 09:28 AM


Assuming you're looking at an '06 type engine, there is only the one O-ring listed to go between the crankcases. There are several places on the outer covers where these are used, however.

Usually, you can spot where they belong pretty easily. There will be a counter bore for the dowel where it belongs, and another step bored into one half or other for the O-ring to sit down in. That last cut out has to be there, or the ring would be smashed flat and interfere with the cases closing up all the way.

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  • finthat

Posted April 11, 2009 - 09:42 AM


Sorry this is on an 03 450. I would assume the same theory would apply to where they belong. I noticed the counter bore and will match them up with the o rings. I will be assembling everything with out o-rings ect. to make sure the tranny and all shift before I make it all permanent. I will match all gaskets ect.up before and make sure I can account for all the seals in my kit as well.

  • grayracer513

Posted April 11, 2009 - 09:59 AM


Sorry this is on an 03 450.

That crankcase assembly also lists only the single O-ring in roughly the same location, and the same layout design principles do indeed apply.

  • finthat

Posted April 11, 2009 - 03:01 PM


Thanks alot, I am sure the other one is from the outer cover I will figure it out made it this far.

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