Sign in to follow this  
Followers 0
Matthew12815

03 YZ 450F intake valve stuck?

9 posts in this topic

Alright, I can say I am truly stumped. and I am asking for help. I have an 03 Yz 450F and the rear intake valve is stuck and it can't go down(with the spring on). it is the intake valve that is closest to the kick-starter. But when I take the spring out the valve moves freely( pretty much no resistance). the valve cap/ bucket has no scrape marks on it(so it's not rubbing). Can anyone help me? They are also new valves the head just came back from a shop(got the guide reamed out). I also checked the valve and it is not bent. Any help?

Share this post


Link to post
Share on other sites

When you say, "cannot go dow." Do you mean the valve will not open or the valve is held open?

Share this post


Link to post
Share on other sites

If the valve will NOT open, the guide may not be totally seated causing the valve spring retainer to hit the guide & stopping the valve from opening.

If the valve is held open with the bucket in place, the bucket could have been damaged while the motor was apart. Possibly stepped on or something to deform it causing it to be somewhat crushed (oval shaped) which could cause the valve to stick. But this would only be the case if the bucket does NOT slide freely in the pocket.

Share this post


Link to post
Share on other sites

The valve bucket slides freely so that's not the case. I can take it off with no problem. But when I put it on and try to push down on it, it wont even budge. I've tried tapping it with a hammer and a wooden stick( put together) and that wont even budge it. I have it booked to go back to the shop I got it from later next week. unless I figure it out by than.

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