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Powervalve stuck? after topend rebuild

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Did a top end today on a 250 xcw tpi.  I cleaned the cylinder with carb cleaner before reassembling. The powervalve wasn't dirty at all to begin with so I didnt tear it apart apart from getting access to the bolt under the cover.  I did spray a bunch of carb cleaner on it though, and on the other side where the other cylinder bolt is located.  I threw some oil on everything when reassembling but now the clawed powervalve assembly unit is kinda stuck in the raised position.  I need to lower it so I can reattatch the powervalve ball joint and close it up.  Did I screw something up or do I need to finesse it to move up and down freely.  I didnt mess with anything in there aside from carb cleaner spray. 

Also- the indexing pins are not letting the newly purchased Slavens S3 mule head seat completely on the cylinder.  They are properly indexed but not seating flush.  Is it a machining issue with the head, or should I just cinch it down with the head bolts? Maybe the piston is too high, but it looks just about flush with the top of the sleeve. EDIT- there is a rubber o-ring in between the head insert and the inside of the head.  Im thinking im assembling this right so maybe the oring just needs to be smushed down.....or maybe i have the oring in the wrong spot, thus raising the head off the cylinder 1.5mm

Edited by N.dica

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To help anyone who might have a similar problem:

I hadnt disassembled the entire powervalve because the outer housings were pretty clean and muck free.  But, since I had to open up the powervalve to get what was stuck unstuck I found out that the inside of the powervalve had a considerable amount of carbon buildup that was undetectable without disassembly. Good lesson here- clean out your powervalve with a piston swap and keep things running fresh.  Id imagine that a fair amount of poorly performing engines are the result of needing a good cleaning.  I only had 65 hours on mine, but it was a lot of slow technical enduro riding so that contributed to the carbon buildup.  Now that it is clean, everything is operating smoothly without a hiccup.

Also, in response to my piston head fitment, I think I was sent a mislabeled 300 head instead of a 250 head.  Waiting til monday to confirm.

Edited by N.dica

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