Hairline Case Crack, HELP!!

i am putting a top end in my 03 yz250 and when i was about to reinstall the jug i noticed a small hairline crack in the left side case half. 0217081919.jpg

the crack is between the arrows in the picture. it carries all the way to the edge near the crank, i dont notice any depth to the crack at all. it seems like a very strange place to have a crack. any input would be greatly appreciated!!

well, you should go to oldschoolyamaha.com ask for scott he will help you out. good luck.

its not a crack its a casting mark.

its not a crack its a casting mark.

Exactly.

It's almost certain that it's just a casting flaw. No need to worry about it.

i figured thats what it was, there is no way an impact would have made a crack there, and even if i overheated the motor to the point of catastrophic failure, it wouldnt cause a crack in that location. i just needed some secondary input to help me sleep better tonight!!!

let us know how she runs when you get 'er together.

As if you needed more confirmation, I just went into the garage and looked at my spare 03 motor. There's a line in that exact same spot. You're all good!

Get some dye penetrant and developer and dab a bit there with a qtip or acid brush. Wait a few minutes and clean it off, spray on the developer and you'll know if there's a crack there. It's probably a casting mark like they said though.

Craigus

Gah, I found the same thing.

We sure it's just an innocuous casting flaw?

photo.php?pid=407625&id=1420197662

Gah, I found the same thing.

We sure it's just an innocuous casting flaw?

Mine looked the same when I did it back in January. Still runnin' just fine. :thumbsup:

Mine looked the same when I did it back in January. Still runnin' just fine. :thumbsup:

That's just not the type of you expect to find when you take the cylinder off...

I'll not worry about it! Thanks!

Did my top end last week as I was pulling on the rod to check for slack noticed three lines in same spot looked like cracks but did not penetrate the surface. Scared me bad but quick check with some YZ buds and they said they were "Yamaflaws" put it back together and it runs better than ever.

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