Milky White paste in my crankcase

4 replies to this topic
  • RaderRider

Posted April 28, 2007 - 07:35 AM


I have a 2004 yz450f and i went to change the oil yester day and when i took off the oil filler cap i noteced some white paste on the plug. so i took the left cover off and it was just pasted in white goo. I dont know if it is my oil that im using it's royal purple synthetic max cycle. any help would be greatly helpfull thanks.

  • Yami450D

Posted April 28, 2007 - 08:17 AM


you got alot of water in the oil I'm thinking, that's what happens to your oil when you get water in it.

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  • rexbond007

Posted April 28, 2007 - 09:49 AM


is this your first oil change this year?
could be condensation left from winter storage.or you have a head gasket leak

  • RaderRider

Posted April 28, 2007 - 10:43 AM


ya thanks ill look into that sombody els said it could be the wate rpump seal too.

  • grayracer513

Posted April 28, 2007 - 01:18 PM


Can't be the water pump seal. If it leaks, the coolant runs into a space between the impeller shaft oil seal and the coolant seal. That space leads out to the hole below the water pump.

The leak points are:
Head gasket
Cylinder base O-ring
Right crankcase cover water passage O-ring

Very rarely, a cracked component or a leaky jacket plug in the cam box.

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