HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
Sean Brodie

zy400f

9 posts in this topic

1999 yz 400f have oil coming out of breather tube on valve cover. I just got this bike was this a problem with the 400.:bonk::thumbsup:

Edited by Sean Brodie

Share this post


Link to post
Share on other sites

If oil is dripping out there's a chance that the bike was over-filled with oil. If you get smoke coming out then you got problems.

Check the FAQ for how to do a proper oil level check and see if it is over-filled.

Share this post


Link to post
Share on other sites

Oil level is in the middle of dipstick and no smoke just lots of oil. Compression was tested by shop thay said it was fine

Share this post


Link to post
Share on other sites

Could be an issue with the drain back to the oil tank from the head. I don't know too much about this area, but hopefully someone with more experience will chime in.

Share this post


Link to post
Share on other sites

Search! This is normal. When you aprk the bike, you will get a bit of a puddle of oil under the breather, maybe an inch or an inch and a half in diameter. You will also get some oil on your left boot. As the engine "breathes", some oil mist is picked up and pumped out the vent along with the air.

Share this post


Link to post
Share on other sites

My '98 YZ400 always has a small drip of oil after a ride, same as Bridy 426 says. I never have to top the oil up beween changes which shows the amount of oil 'lost' is minimal. In fact I would now be more concerned if there was no drip after a ride.

The key point here is, how much oil is coming out. This was not clear in the post.

Share this post


Link to post
Share on other sites
Is this a normal 400 thing, cause it never happens on my 2010??? :thumbsup:
The 2010 models have a baffle built into the venting system.

Share this post


Link to post
Share on other sites

Did you start the bike first and check the oil correctly ?

When I first got my 426, the oil was in the middle of the dipstick also, and it had a lot of oil out of the breather tube. but after checking it by the proper procedure, I found out It was WAY overfilled.

Make sure you follow the proper procedures !

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0