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.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 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.

Related Content


Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

BIGBORE FOR YZ450F 2006? by Taattie94

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.