YZ426 oil overflow leak????

2 replies to this topic
  • Serenity Now

Posted May 10, 2005 - 07:25 AM


I've got a 2000 426 that I was jumping yesterday and after about 10 jumps (no hard landings) I noticed some smoke coming from front of engine. After further investigation it appeared to be a small amount of oil dripping from the black tube at the front of the frame. I assume this is just some sort of overflow tube? It was just a slight drip but I figured when I was jumping it splashed on the engine which caused the smoke. Should I be worried, is this normal? My 99 WR400 has never done this. I checked oil level and everything was fine. Any ideas? :)

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  • grayracer513

Posted May 10, 2005 - 07:55 AM


That's the crankcase breather. When you run the engine fairly hard, "blow by", combustion gases that have forced past the rings, will escape through that tube and carry a small amount of oil vapor with it. It's normal to see a few drops come from the breather after a good run, and as long as the engine isn't using a significant amount of oil, it's nothing to worry about.

  • Serenity Now

Posted May 10, 2005 - 08:08 AM


Thanks for the info. I did a forum search and found that it's not as big of a deal as I thought it may have been. Others asked the same question many times (I should have searched before posting I guess). It just worried me that it never did that before and my WR has never done that.

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