Waterpump weep hole leaks intermittently

6 replies to this topic
  • gerbrony450

Posted November 01, 2007 - 12:46 PM


I replaced my waterpump impeller and bearing assembly and gaskets about five rides ago, after my waterpump went out on my 04 yzf450. After replacing it I have ridden it about 5 times maybe put 300 miles on it since then. I started it this weekend and the weep hole leaked intially when fired the bike up and eventually stopped leaking after it warmed up and I rode it for a while. I started it cold again today and it did the same thing, leaked, then stopped after it warmed up and rode it for a bit. Has anyone had this problem even after replacing everything? Any feedback is appreciated.

  • grayracer513

Posted November 01, 2007 - 05:04 PM


Did you replace the shaft?

  • 642MX

Posted November 01, 2007 - 07:47 PM


Its important to replace the shaft when you swap the bearings and seals, the seals cut a groove in the shaft.

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  • gerbrony450

Posted November 02, 2007 - 09:11 AM


I actually did replace the shaft, impeller and the bearings. Added a new gasket too, thats what is puzzling.

  • grayracer513

Posted November 02, 2007 - 09:32 AM


Which way is the lip of the coolant seal (the outer one) facing?

  • kippieland

Posted November 03, 2007 - 09:20 PM


The same thing is happening to my 03 YZ450F but I have never changed the waterpump or anything like that. I am very puzzled since I haven't toughed anything.

  • kippieland

Posted November 03, 2007 - 09:47 PM


Hey, I found a thread with '06 YZ450F with the same problem. They were saying it due to the colder weather. That makes sense to me.

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