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Cylinder head damage

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Just pulled the valve cover off and noticed some scratches inbetween buckets on the intake side. Any ideas if this is a major problem and what i could do about it if so? Thanks. Pictures below.

20170730_215154.jpg

20170730_215055.jpg

Edited by Scottwr12345

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What engine is that? That appears from the picture to be the cam journal? That's called galling, and it's a result of lubrication failure. That head is now trash.

Time for a new head and probably cam, and you need to resolve the lubrication issue. Did the bike run for a while upside down after a crash? Did you not change the oil often enough? Not an appropriate oil for the engine or seasonal temps?

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I've had my share of 4 strokes, so this is an educated response........ go get a 2 stroke start mixin gas an slappin ass

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Its an old 01 wr250f. Bought it used and i assume it was abused prioir to me getting it..when i bought it it had way to much oil in it, was a steal though. Yes its the cam journals, the cams themself look perfect its only the intake journals. No possible way to machine them i guess... 

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6 hours ago, Scottwr12345 said:

Its an old 01 wr250f. Bought it used and i assume it was abused prioir to me getting it..when i bought it it had way to much oil in it, was a steal though. Yes its the cam journals, the cams themself look perfect its only the intake journals. No possible way to machine them i guess... 

Four stroke heads are considered consumable items. Unfortunately Yamaha heads are pricey, that WR Head is probably at least $500.

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Damn it.. not sure if its worth rebuilding or not.. i also need to replace the kickstart assembly and piston/cylinder. Im worried if i split the cases there will be more damage due to the fact there must have been a lack of oil at some point in the top end... any ideas how it could have happened if my oil pump is working fine and oil levels have only been over filled never under? Thanks for all the help so far.

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Pretty sure if ever the bike has ever been dumped on it's right hand side with the engine running at higher rpms,

the oil pump can loose prime and start pumping air.

 

It's a used bike with no past history, following an earlier failure

the oil pump could have been replaced just to get the engine running for the next guy to buy it (unfortunately you)

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This is 100% repairable and for not much money. Just sent my head to Engine Dynamics and had it repaired. This is not lubrication failure, this is over torquing of the cam caps after a valve adjustment. Either way it can be easily and cheaply fixed, and the fix prevents this from happening I the future. Pop the head off and mail it in. You'll have in back in less than two weeks all fixed up and better than factory.

 

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Damn it.. not sure if its worth rebuilding or not.. i also need to replace the kickstart assembly and piston/cylinder. Im worried if i split the cases there will be more damage due to the fact there must have been a lack of oil at some point in the top end... any ideas how it could have happened if my oil pump is working fine and oil levels have only been over filled never under? Thanks for all the help so far.

 

Not a lubrication failure.

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Either way im gunna part out the bike and if possible swap the gears out of my yz 250 if the wr gears are in good nick. Thanks for all the replys guys really appreciated.

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19 hours ago, 0macman0 said:

 

Not a lubrication failure.

That most certainly is lubrication failure, whether it be from loss of oil pressure or lack of clearances due to improper torque or overheating. The loss of oil film and boundary lubricant resulted in metal to metal contact that allowed the aluminum to microweld itself to the steel camshaft and tear away from the head.

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That most certainly is lubrication failure, whether it be from loss of oil pressure or lack of clearances due to improper torque or overheating. The loss of oil film and boundary lubricant resulted in metal to metal contact that allowed the aluminum to microweld itself to the steel camshaft and tear away from the head.


Touché. Just saying it probably wasn't lack of oil pressure.
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Just now, 0macman0 said:

 


Touché. Just saying it probably wasn't lack of oil pressure.

 

And your analysis is probably spot on, based on your experience with a similar issue. It's why I said in my first post to investigate the cause of the lubrication failure. Had it been a loss of pressure there would be other telltale signs in the engine, a lack of other signs would point in a direction like what you stated.

 

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I'm surprised how common this is on these bikes. I have to speak highly of engine dynamics though they will fix you right up quick.

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