oil in the cooler

[carlsberg]

dirt bike went hot on a race.

When I got home and would empty the cooler, I found that there was oil in the cooling water around 0,1qt water / oil in the cooler.

Someone who knows what is broken?

when I removed the cylinder, I saw that Crank Shaft had become blue.

do I need to change Bearing?

it is a Yamaha WR 450-08.

grateful for a response

Robert

[jj546]

I would consult a reputable dealer with your question. It would take a high pressure oil leak to overcome the pressure in the radiator. My guess is in the head or possibly at the water pump shaft/seal.

Let us know when you find out.

JJ

[buggs bunny]

maybe a cracked head,the crank is supposed to be blue i have seen pictures of new ones.

show pictures for better answers.

[carlsberg]

now I have talked to the dealer.

when there is oil in the cooler is the gasket to cylinder head that are broken.

when crank shaft start changing color,

then you have to replace the rod bearings and main bearings.

Robert

[timoyz1]

now I have talked to the dealer.

when there is oil in the cooler is the gasket to cylinder head that are broken.

when crank shaft start changing color,

then you have to replace the rod bearings and main bearings.

Robert

Bull. My crank was blued brand new. If the bearings operate freely, and there is no freeplay, run it.