This came from engine vent line on WR400?

Im in the process of putting back together my WR400 when I found this problem. The engine vent was run into the air box so I disconnected it. When I did this oily brown liquid came from the line. In all the years of riding Ive never seen this before. Does anyone have an idea of what this is? Maybe the hose was collecting oil and water got in it? Not sure.

camefromventhose.jpg

Im in the process of putting back together my WR400 when I found this problem. The engine vent was run into the air box so I disconnected it. When I did this oily brown liquid came from the line. In all the years of riding Ive never seen this before. Does anyone have an idea of what this is? Maybe the hose was collecting oil and water got in it? Not sure.

camefromventhose.jpg

Thats a combination of 'blown-out' engine oil, and water. It is normal

The engine vent usually runs straight down behind the left side radiator. Some people route it to the air box to filter it and prevent suff from getting sucked it.

There was probably a "low" spot in the hose that was able to collect oil and condensation. If so, you might try to eliminate it if you can, or you could splice a T into the low spot and drain it regularly.

I left mine alone. Others may not agree, I can't imagine much vacuum in the crankcase. In a perfect seal the pressue and vacuum would be equal, but any blow by will add to the pressure side, so most of the time there would be a little pressue and less vacuum.

that's a little more than what you see normally, however, like stated - a small low spot would easily collect that much in a few ride's time. And it always comes out looking milky.

If you want to verify everything is good - just pop the lid off and you'll see it's all ok under it.

Thanks guys thats what I thought but I figured I would ask just to be sure. This is a supermoto bike I purchased last Nov. so Im not sure how long the line was run into the airbox but based on the oil in the box I would guess a long time.

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