03 YZ450F losing coolant thru the little hole behind the water pump

3 replies to this topic
  • smokingtz

Posted April 07, 2011 - 05:52 PM


Does this mean a seal is bad? Does the side cover (including clutch, etc..) have to come off to fix? I had popped a head gasket and after fixing that I noticed the leak on start-up. I might have lost coolant and overheated it. Head checked out fine so I'm hoping for the best.

  • primerib108

Posted April 07, 2011 - 06:06 PM


Could be just the seal....or, could be the impeller as well. Run your finger nail down the shaft and if it catches (you will feel the ridge) then you need to replace that too. My 06 did the same and it is pretty straight forward to fix.

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  • grayracer513

Posted April 07, 2011 - 06:57 PM


Water pump seals. Check the shaft like he said.:


  • smokingtz

Posted April 09, 2011 - 09:42 AM


Thanks. Was just the seal.

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