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searching for lost valve shim. suggestions?

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2007 450 SX-F. cam went out of time (guessing hydraulic chain tensioner failed, as I hear they are notorious for failure).

exhaust valve spring retainer broke in half, both collets came out and the valve guide broke off a chunk. other top end damage, but I won't tell you my sob story for fear you'll hack your wrist.:)

I found what looks like the mushed up collets, the two halfs of the broken retainer (thanks KTM....I can't just buy a new retainer, I have to buy complete valve spring assembly :banghead:). When I took pipe off, I found a chunk of the valve guide rattling around inside, and I also found a small chunk of valve guide on top of piston. I have NOT found the valve shim. I think i have everything else.

I have engine out. This was the exhaust valve, nearest the timing chain. I thought it might fall down through the valve chain area. I removed chain guides. I thought the shim might stick on the magneto (once on my 525 KTM, the decompression lever broke and I found the broken chunk

stuck to the magneto). Magneto cover is off, and nothing on the magneto. I have drained oil and strained it, can't find the shim. Searched with a light, magnet (where I can fit it), etc.... I shake engine but can't hear it rattle.

Is it possible it blew out exhaust as all this damage happened? Any other nook/cranny it might stick in down below? I don't want to re-assemble and have that hardened steel shim grenade around.

Can I put in oil plug and add some solvent, then shake it around and drain it? Would solvent hurt anything?

Oh yeah, I am trying to remove oil pump to see if that shows me anything, but it seems to be very sticky to pull out. Am I missing something on that?

Do I need to remove the clutch cover to fish some more?

Any suggestions?

THANKS!!:lol:

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So, you havent opened up the engine? ..I would split the case and check everything when engine is on the table. It is not that big of a job. Just to be sure. When disassembling, clean and check every part for damages. And if everything looks ok, just assemble it. Im not that great engineer, but Im just thinking that when something like that happens it could break stuff inside the engine. :lol:

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i know you're probably right, but i was hoping for a magical, easy solution. splitting cases looks like a big, intimidating job.

ITS NOT

I just make sure its on its side and keep all the gears/spacers/etc where they belong.

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can I get away with only removing one side, or do both sides have to be stripped apart?

any particular side you lay down?

I guess I'm worried about not recognizing which gears need to be lined up/timed properly, or being out by a tooth. I think the starter drive gears don't need to be timed, but all the other gears have to be perfect (??)

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You can pull off one side. When you do use duct tape to tape up all the gears and shift forks so they stay in place till you are ready to re assemble. At least that worked for me.

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YIKES!! :):lol: I can take anything apart, but putting it back together without a mistake and getting it all correct might be a different story. sure wish I found that valve shim stuck on the magneto. Sonic makes it look easy, but I'm sure he's had many of these apart before.

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Oh, and you need some tools also. Like flywheel puller, few torque wrenches and machine shop manual. With manual you get almost everything you need to know to build the engine.

First time I did it.. I can say I was scared. I prepped myself for it by cleaning my garrage. Making everything easy as possible. Disassembling the engine in a line of parts on the table. So when I start to assemble it, I just do everything in the other way around.

Oh, and my engines are running, still. Just need to do a big rebuilding during the winter to make it more like racing machine again.. little soft at the moment. :lol:

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You need a deep well 36mm socket to get the primary nut off.

Have you taken the head off yet?

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head and cylinder are off. head is at the machine shop. it's only that missing valve shim that causes me concern. It'd be really nice to find out from others if they ever lost and then found valve shim somewhere. I would have thought it would have been loose at bottom of crankcase/drain hole after I shook up the engine.

I was wondering if i filled crankcase with solvent or diesel fuel and shook it around, if that might rinse it loose. And I'm still assuming it's in there. It could have went out the exhaust, like the chunk of valve guide that I found in exhaust pipe.

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:banghead::):thumbsup:b WOO-HOO!! I found it!!

My son is in the middle of an axle swap from F250 TTB, to F350 solid axle. THe TTB is sitting on jack stands and I'm removing the better brake backing plates. I'm wailing away on the spindle and see a shim on the floor. I thought it fell out of the axle and had something to do with that. It sorta looked like a valve shim. It was nowhere near where I did the work on the bike; opposite end of my shop. AND... I swept floor after I started bike disassembly before I started the shim hunt), so I thought it would have been swept up and thrown out if it had accidentally fallen out.

I guess it fell out while I was removing head (while engine was still in frame :cheers::doh::lol:...don't try that at home kids..stoo-pid-me). I never noticed, must have been inadvertently kicked around my shop for 2 weeks, until it magically appeared!! flukey, but also a huge relief.

I bought the rotor puller tool. I think I'll still pull rotor to see if any other metal crept inside the blind crevice. then I'll be satisfied that I'm good to go.

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