2006 Yzf450 water getting in the oil

6 replies to this topic
  • NZ_Northlandrider

Posted August 29, 2016 - 11:12 PM


Hi guys my my yzf450 2006 is getting water in the oil, I fill up the radiators and within two minutes of riding they are empty again. It had a top end about 5 hours ago using Cometic gaskets and i have just replace the water pump seals. Do you recon the head gasket could already be blown? any help would be much appreciated.

  • damnbiker94

Posted August 30, 2016 - 02:46 AM


Was there any grooving on the water pump shaft? Also did you replace the water pump bearing and BOTH seals?

  • grayracer513

Posted August 30, 2016 - 10:02 AM


The water pump cannot pass water to the oil because there is an escape port located between that seal and the oil seal.  It's the "weep hole".  When coolant leaks past the seal, it goes outside to ground.


Water (coolant) can enter the crankcase from only 3 places, absent a crack or hole in a piece of hardware: 

  • Head gasket
  • Base Gasket
  • Right crankcase cover, water passage seal


How did you torque the head?

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  • NZ_Northlandrider

Posted August 30, 2016 - 11:06 AM


Hi there was not any grooving on the propeller shaft and yes i replaced both seals and the bearing, i torqued the head bolt to the recommended amount in the manual,and i replaced the side case gasket, it sounds like it is head gasket, i will hopefully check it out tonight :facepalm:

  • NZ_Northlandrider

Posted August 30, 2016 - 11:44 AM


To clarify the whole story, My bike was running good then i noticed the water level would go down after about 20 mins but it would only go down a bit so i kept topping it up and at the end of the day i noticed water pouring out of that hole grayracer513 said so i replaced the seals bearing and shaft, the radiator was only half full when i noticed could i  of cracked something alowwing water to escape, or do u recon its the head gasket

  • grayracer513

Posted August 30, 2016 - 12:18 PM


So, then, you first torqued the four main head bolts to 22 ft/lbs, then you removed and re-lubed them and torqued them back to 14 ft/lb, and after that, you tightened each of the four main bolts  1/2 turn farther in two quarter turn steps?




The head gasket is the likely culprit, although it could be any of the three causes I listed.  There is no O-ring at the water passage in the steel shim base gasket, so it's quite important to replace it also, whenever the head has been removed.

  • NZ_Northlandrider

Posted September 09, 2016 - 01:12 AM


Hi guys i pulled apart the top end and sanded the head and cylinder then replaced the head gasket with a cheap tusk one. it no longer is using water and i can notice a power increase. 

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