Blows white smoke/steam out oil breather?

2 replies to this topic
  • Tevonini

Posted April 02, 2013 - 09:26 PM


Hello all, I need help I have a 2000 yz426 which most of you probably already know because of my tons of questions I ask about it but her goes another one,
Ok I just learned how to ride a track so i stead of fast paced single track I usually ride I've been kinda hooked on the local mx track any ways I went out there after work today and road the track it's a real mello track no whoops or tripples it's all table tops and little step downs but any ways
I road for about 3 hours today with about 10 minutes on the track 5ish off give or take my trail tech vapor said was always between 170 and 195 I watch it pretty religiously because I just put a new piston in it because I got her too hot.....
So after riding about 2 hours I watched some guy fall so I turned around and made sure her was ok and continued to BS with him and when I went to start it I thought I was seeing things when I kicked her over white smoke/steAm came out of the bottom of the engine but she fired up second or third kick like always so I didn't think any thing of it but when I was loading the bike an hour later I happen to kick it over and see the smoke again so I investigated.... It was comming out the vent hose out of the valve cover.... So I slowly kicked it over and every kick a puff came out but then she fired right up, and the smoke went away while running..... So I killed it and checke the oil when I unscrewed the dip stick a little tiny bit of this whit stuff came out the oil tank.. So now I'm totally confused but the oil was except an level(about 3/4 up between low and full on the dipstick if not 7/8) please help this have me stupped thanks in advance tomorrow I'm going to pressure wash the mud off and ill do some more investigating

Oh ps I did wash out about 15-20 min befor I noticed the white smoke the bike laid over on its right side(kick starter side) and ran for about 8 seconds befor I jumped up off the ground and killed it

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  • grayracer513

Posted April 03, 2013 - 06:59 AM


It's normal, in most cases. The smoke is hot oil and crankcase vapors being pushes out as the piston moves down in the cylinder. If you aren't loosing coolant and aren't using a lot of oil, and the oil isn't being contaminated in some way by the coolant, there's nothing to be concerned about.

  • Tevonini

Posted April 03, 2013 - 08:07 AM


Cool thank you so much grey I apreciate it alot

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