oil in air box

[towens]

My 2006 nytro er I has a clear line on the vapor recovery line going from the air box to the crankcase. At low rpm"s it pumps oil up to the air box, should it not just be vapor going to the crankcase?

 

[thor452]

is the oil over filled?

 

[towens]

thank you for the reply, no, the oil level is checked per yamaha instruction, the recovery line has no kinks, and the motor is sound, leak down check is good.

 

[thor452]

intresting i am sure some one has come across this before and will chime in.

 

[towens]

I do not know the function of the valve that the oil lines all connect to coming out of the oil tank and going to the motor and air box, however I want to believe it some sort of check valve which could be malfunctioning, or there is some valve in the vapor chamber in the air box that is not functioning as designed. Does anyone know how they work?

 

[Stubbs]

This is normal on a three holer with carbs. Ask anyone who has left that hose off of the bottom of the airbox in error about the mess it makes. Also the reason three holers didn't have filter kits available for quite a few seasons when these sleds were carbureted.