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I bought wr 250 project. Previous owner said it had been rebuilt but wouldn't run. I found out the base gasket was leaking pulled it apart and replaced the gaskets. Now the power valve cover won't go down far enough to line the bolts up. Engine code is 4jw jug is 4jx00. Po had every thing junked up bolts missing etc. Am I missing something?

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5 minutes ago, beadrunner said:

 

I bought wr 250 project. Previous owner said it had been rebuilt but wouldn't run. I found out the base gasket was leaking pulled it apart and replaced the gaskets. Now the power valve cover won't go down far enough to line the bolts up. Engine code is 4jw jug is 4jx00. Po had every thing junked up bolts missing etc. Am I missing something?

 

WR250 project. Check

PV fitment. Check

Year?

Photos to help see what it is you are looking at?

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I think the cylinder was decked, as in some shaved off the bottom. When this is done, the cover needs to be shaved with it. Plus there is a ruber piece that goes between bottom.

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1 hour ago, beadrunner said:

PO had every thing junked up bolts missing etc.

If this is the case, I would want to take it slow and easy and check everything out. I would rather fix it before it becomes a bigger problem. Initially it will take longer, but it will give you peace of mind and a much more reliable ride.

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Should I worry about the deck height and if so what is the best way to measure it. Also the rubber gasket was cut into like they had put the cover on and then tightened the jug down

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There was a long rod kit sold for that engine back in the day. I have one installed on my 93 yz250. It uses a 5mm spacer under the jug to make up for the 5mm longer rod. It also came with a power valve cover that is 5mm longer. I think that is what you have. If that is the case I'd be more than happy to trade you for a stock one.

 

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8 hours ago, Bricktop72 said:

There was a long rod kit sold for that engine back in the day. It uses a 5mm spacer under the jug to make up for the 5mm longer rod.

That was my thought, too. Yamaha had 2 or three different power valve linkage covers of different lengths -- I think the '88 version was longest because that motor ran the longer rod stock. So if you went with a Long-rod mod, it was paired with the longer cover (along with the cylinder base-spacer). Not all of the mounting holes lined-up, and the fit wasn't perfect, but it wasn't something a little silicone couldn't fix. At least it was that way on our '96.

It could be that you just need a (shorter) linkage cover from a later bike. Notice the different shape on the covers...

http://www.ebay.com/itm/1990-Yamaha-YZ250-WR250-POWER-VALVE-LINKAGE-COVER-Side-Cylinder-/142349977337?fits=Model%3AYZ250&hash=item2124b846f9:g:rPAAAOSwTM5Y8iLo&vxp=mtr

http://www.ebay.com/itm/1992-Yz-250-Yz250-Power-Valve-Linkage-Cover-and-Grommet-Gasket-91-92-/332188918220?hash=item4d5800a1cc:g:nBgAAOSwZQRYgAGt&vxp=mtr

http://www.ebay.com/itm/88-yamaha-yz250-yz-250-powervalve-rod-linkage-arm-cover-6417-/142270311184?hash=item211ff8ab10:g:L-sAAOSwUKxYmO0E&vxp=mtr

http://www.ebay.com/itm/EVO-YAMAHA-YZ250-1983-cylinder-linkage-cover-int-dze-Zylinder-Abdeckung-/162465638366?hash=item25d3b4e7de:g:SlgAAOSwux5YYADI&vxp=mtr

Good luck, and let us know what you find. :thumbsup:

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14 hours ago, CaptDan said:

That was my thought, too. Yamaha had 2 or three different power valve linkage covers of different lengths -- I think the '88 version was longest because that motor ran the longer rod stock. So if you went with a Long-rod mod, it was paired with the longer cover (along with the cylinder base-spacer). Not all of the mounting holes lined-up, and the fit wasn't perfect, but it wasn't something a little silicone couldn't fix. At least it was that way on our '96.

It could be that you just need a (shorter) linkage cover from a later bike. Notice the different shape on the covers...

http://www.ebay.com/itm/1990-Yamaha-YZ250-WR250-POWER-VALVE-LINKAGE-COVER-Side-Cylinder-/142349977337?fits=Model%3AYZ250&hash=item2124b846f9:g:rPAAAOSwTM5Y8iLo&vxp=mtr

http://www.ebay.com/itm/1992-Yz-250-Yz250-Power-Valve-Linkage-Cover-and-Grommet-Gasket-91-92-/332188918220?hash=item4d5800a1cc:g:nBgAAOSwZQRYgAGt&vxp=mtr

http://www.ebay.com/itm/88-yamaha-yz250-yz-250-powervalve-rod-linkage-arm-cover-6417-/142270311184?hash=item211ff8ab10:g:L-sAAOSwUKxYmO0E&vxp=mtr

http://www.ebay.com/itm/EVO-YAMAHA-YZ250-1983-cylinder-linkage-cover-int-dze-Zylinder-Abdeckung-/162465638366?hash=item25d3b4e7de:g:SlgAAOSwux5YYADI&vxp=mtr

Good luck, and let us know what you find. :thumbsup:

Damn your good! 

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