03 YZ450f Exhaust Valve Seats Pitted

2 replies to this topic
  • Koth442

Posted January 14, 2015 - 06:00 PM


My exhaust valve seats are pitted very badly. Leak down test cued me towards a large leak out of the exhaust.


It seems my options are:

1. Get another head, either new/used

2. Replace valve seats.

3. JB weld that bitch and grind them back down (joking)


It seems vavle seats should be replaced by a repuitable shop. Any idea how much that would cost? Any other clever ideas? Any body got a 03-05 head they want to sell?


Open to other comments



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  • grayracer513

Posted January 15, 2015 - 07:17 AM


Have the head evaluated by a local shop that does work for the area dealers, or send it out to Engine Dynamics.  They can fix heads with seized cams, or that have dropped valves for much less than the cost of new.

  • Koth442

Posted January 18, 2015 - 01:42 PM


Gray, thanks for getting back to me.


Local Head & Block Repair said the pitting is too deep for grinding or cutting. I'll give Engine Dynamics a call. It just needs valve seats replaced. Also looking into a replacement used head in good condition.

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