03 Yz450f Oil filter screw

Hey guys I need some help. My bottom screw on my oil filter cover stripped out. So it's leaking oil pretty bad. The fact that its an allen head and the other 2 aren't makes me think it wasn't the original anyway. So I need to know what size and thread pattern the screw should be. Anyone know?

You need to do a search on this.

It's a common problem on the older motors.

There is a process for cleaning out that threaded cavity before putting your screw back in, to prevent this from happening.

The debris from the filter clogs the threads, forcing it to strip.

Thanks man. The search on my phone never works right. I always try but never get the right results. It's weird.

You posted this in the wrong forum, so it's been moved.  The problem of the stripped lower oil filter bolt is well known, and applies to all YZF models up to the 2010 YZ450.  As far as I know, the issue still exists on the 250F and WR models.  The problem is not so much that the threads weren't cleaned out before you put the bolt back, it's that they were contaminated when the bolt was unscrewed:




The original bolts were all three Allen bolts, and the lower one should be a shouldered bolt, if you want the cover to align correctly and not obstruct an oil passage.  The part number for the correct bolt is 90109-065G2-00.


Had you done something about the matter ahead of time, it could have been prevented:




But, now that it's already stripped, blocking off the drain passage will likely not be needed, but read a little of both threads so that you understand the issues involved.  If you use a thread repair insert to correct this problem, be absolutely certain that it's long enough that it closes of the drain port that crosses into the threads.  Otherwise, you will loose oil pressure and damage the engine severely. If you're in doubt of whether the passage was completely closed or not, or if you find out after installing it that it doesn't reach that far, do the mod shown in the second link I posted.

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