Water in oil


10 replies to this topic
  • nor-calYZ426

Posted January 01, 2010 - 05:44 PM

#1

02 yz426f gettin water in the oil. Drained the oil, put new oil in, refilled with coolent, ran bike for 3-4 minutes and all the coolent went into the oil. Bike runs fine, no loss in power, idles fine. Oil is milky white color. The guy i bought the bike from said water pump was just replaced. What do you guys think? Head gasket? waterpump?

  • Forddriver45

Posted January 01, 2010 - 06:05 PM

#2

sounds like the water pump . If it was the head gasket it would be hard to crank and have a wet plug lol mine did.:moon:

  • nor-calYZ426

Posted January 01, 2010 - 06:10 PM

#3

yea, i was thinking it would run crappy if it was a head gasket

  • grayracer513

Posted January 01, 2010 - 06:37 PM

#4

sounds like the water pump . If it was the head gasket it would be hard to crank and have a wet plug lol mine did.:moon:

The water pump can't do that, unless some "genius" decided to block off the coolant escape port.

The possibilities are:
  • Head gasket
  • Base gasket and O-ring
  • O-ring at the right crankcase cover
  • Cracked cylinder
  • Cracked head


  • nor-calYZ426

Posted January 01, 2010 - 06:53 PM

#5

Could it be the oil seal behind the water pump?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Forddriver45

Posted January 01, 2010 - 06:55 PM

#6

If the seals in the water pump go out it will pass water into the oil.:moon:

  • grayracer513

Posted January 01, 2010 - 11:24 PM

#7

If the seals in the water pump go out it will pass water into the oil.:moon:

Sorry, it absolutely won't. There are two seals, one for coolant, and one for oil, with a gap between them connected to a port that leads straight down and out under the water pump. This is done specifically so that there is no chance of a leaking coolant seal contaminating your engine oil.

You can replace the water pump seals all you want, but it won't fix an oil contamination problem unless the case cover is leaking at the O-ring.

Posted Image

  • nor-calYZ426

Posted January 02, 2010 - 09:42 AM

#8

I'm going try and find a diagram and see if changing the o ring helps. If that dont work it looks like I'm doing a head gasket. Thanks for the help

  • Forddriver45

Posted January 02, 2010 - 10:26 AM

#9

It will pass water into the oil if the shaft is f*** it will let water into the motor ive seen it first hand.

  • grayracer513

Posted January 02, 2010 - 03:28 PM

#10

It will pass water into the oil if the shaft is f*** it will let water into the motor ive seen it first hand.

No, it will not. Sorry.

  • nor-calYZ426

Posted January 02, 2010 - 05:27 PM

#11

I MAY have found the problem. 1 of the 8mm case cover bolts is striped out right next to the O ring. Having that fixed in the morning and if it still gets coolant in the oil its a head gasket. I'll let ya know if thats the problem. Thanks guys





Related Content

Forums
Photo

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
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

2016 YZ450 by CaptainKnobby


Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies
Forums
Photo

James Stewart back on a YZ450F by YamaLink


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies
Forums
Photo

Snake pit oct 30th by The Anvil


Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies
 
x

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.