03 YZ 450 / Oil dripping out

Hey Guys, need some help, went out yesterday Barstow bout 95deg, no biggie. oil would not stop leaking out. couldn't find from where? lower RH side of radiator, crank case, frame directly front of header, all over the place. opened the dip stick hot just after running, seemed to be over filled. if over filled? where does the breather tube go? what happens to the oil if over filled? :thumbsup:

I have an 03 WR 450 but the motor is basically the same . The large breather tube usually just drops down from the top of the head/valve cover along the front side of the frame and motor. Trail riders who cross larger creeks may route this up along the top of the frame and into the airbox so as not to suck up water if the engine stalls and runs backward.Overfilling will cause oil to come out of here. Oil may also be coming from the small bolt on the upper right hand side of the engine.This bolt taps into an oil gallery and could be loose or missing. Check too behind your shifter and counter sprocket. Good luck.

Check the decompression plug. If there is not a little rubber plug on the top ride side and just an open hole, that is your problem. I blew mine out of my YZF and had the exact same symptoms you are describing.

ktmr is right. this is a well know problem. i had the same problem with my 04. it looks like it is leaking all over the bottom of the right radiator right? the spot where there used to be a decompression lever in the head has a plug that has popped out. Get an aftermarket aluminum plug at the TT Store. The aftermarket one is designed to be retained into the head by the stock bolt. :thumbsup:

decompression plug is right.

I just bought and replaced mine.

It came out and oil was on my front frame and right radiator.

Replaced the stock plastic one with a aftermarket plug.

Works great better than stock, no more coming back out

With the screw that holds it in.

Definitely the decompression Plug. They should have recalled that back in 03.

You guys are awesome, I remember seeing that blank hole w/ the set screw.

Now I know what to do.

Thanks All, :ride::applause::thumbsup:

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