08 450

3 replies to this topic
  • SomeSortOfThing

Posted June 04, 2016 - 05:49 PM


Hello! Just picked up a used 2008 yz450 f that is, overall, in great condition. My last two rides, the bike was leaking coolant bad (no coolant in oil, though). Did some digging around on here and YouTube, and seems the seal and impellar shaft like to go out on these. Anyways, got a water pump seal replacement kit (inner and outer seal, o ring that goes to the water inlet, and crankcase gasket) and got it all buttoned up Wednesday night. As soon as I put coolant in, it just starting pouring out from what looked like between the cases (bike was off). Took it back apart today and everything seeeeeemed to be installed correctly, and the impeller shaft looks really good. Now, here is my issue: when the bike is sitting on the stand, it doesn't leak. When I tip it to the right, it doesn't leak. When I tip it left though (shifter side) it starts running coolant from, as far as I can tell, that water inlet from the radiator hose. This is when the bike is on OR off. I am getting incredibly frustrated and would like any help or ideas.




  • SomeSortOfThing

Posted June 05, 2016 - 08:13 AM


Here's where it's coming from. Doesn't look like anything is coming from weep home but it's hard to say

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  • xcbuckeyeguy

Posted June 05, 2016 - 01:29 PM


There's a rubber o-ring that seals the inlet tube where the coolant is laying in the picture. That's where I would start.

  • SomeSortOfThing

Posted June 05, 2016 - 01:31 PM


^^ 3 different o-rings later I found one that sealed it. Thanks

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