WR450 Head repair advice

3 replies to this topic
  • hafte

Posted November 25, 2012 - 09:24 AM


HI all,

I started general engine repair of my WR450, and need advice according a cylinder head.
I has filled the head with liquid and there is no leakage. Only one valve has a little.

The valve seats looks ok for me.
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The 4 valves looks not so bad
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Only one valve looks bad. It has a small fluid leakage
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The comparison between valves.
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I need your advice how to proceed, and save some money:
1. To buy one new intance valve and replace the damaged as is.
2. To buy all 5 valves and springs and replace them.

When replacing do i need seat cutting/replacing or only to lapp with new valves?

Those the Ti valves can be lapped? In manual was written "After refacing the valve seat or replacing the valve and valve guide, the valve seat and valve face should be lapped.", but some users sad that if lapped, life of Ti valve is shorted dramaticaly.

  • n16ht5

Posted November 26, 2012 - 08:31 AM


I would either buy one new valve and see how it goes back together, or just cut new seats and do them all. I have heard not to lap ti valves too, but I have not tried.. nor would I.

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  • tomerb

Posted November 26, 2012 - 07:45 PM


If you read the manual a little closer it says not to use the valve if you used it to lap the seat. After lapping you throw it away and install a new valve.

  • hafte

Posted November 29, 2012 - 03:45 AM


Tomerb thanks for the info.
I was missied this important point, that will solve my problem.
Now i can use one of the old valves for lapping, and put 5 new.


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