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Old 11-27-2010, 04:35 PM   #11
dentheman
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Re: Engine Seized - Please Help

My guess would be that it is repairable if you are mechanically inclined, using the parts manual and maintenance manual on this forum. I imagine a shop would charge a pretty penny to fix it. If you do repair it, check to be sure no bits and pieces went into the oil pump. As far as sludge on the sight glass, I am trying to think what would cause sludge in the oil besides water. Even gas getting into oil will just thin it, I believe. Could moisture from the air box be running down the breather tube?
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Old 11-27-2010, 05:14 PM   #12
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Re: Engine Seized - Please Help

Nice tear down and pics. Although I am not familiar with the internals of the engine I will take a guess at the broken part. You may have a broken cam chain tensioner and/or guide mechanism. Probably replaceable and not as costly as an engine rebuild but I am not sure how far the engine needs to be torn down to do the deed. Pure speculation here but you may have to remove the head and cam shaft to free up the chain enough to replace the tensioner. Please remember I am really good at assuming all sorts of stuff and am generally wrong.
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Old 11-27-2010, 05:24 PM   #13
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Re: Engine Seized - Please Help

I believe you have found your problem.I also think you are right in assuming that a piece of the plastic is jamming the engine.I'm with "Dentheman" that if you went this far you can repair it yourself.The sight glass may have got sludged up by neglect by a previous owner.Good luck and keep us posted.
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Old 11-27-2010, 05:58 PM   #14
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Re: Engine Seized - Please Help

Peter, go to Ron Ayers Motorsports and look at the Fiche diagrams for a little more of an idea what might be broken. Also get some prices for parts as they are quite reasonable from what I have heard.
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Old 11-27-2010, 08:00 PM   #15
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Re: Engine Seized - Please Help

Thank you all very much for the replies and help. I have priced out what I think I may need to fix the obvious problem with the cam chain guide. What worries me know is what I find under the valve cover, which I'm thinking I will most likely have to take off to retrieve all of the plastic - based on what I can see with a flashlight looking up into the head there are plastic pieces higher than I can reach with any tool I have. My big question is can the valve cover be taken off without removing the engine from the bike. Clearance between the head and the top tube seems minimal at best so I'm worried I will have to drop the engine in order to get a look at the camshaft. Does anyone know if you can remove the valve cover without removing the engine? Or can I at least lift it up enough to get a look at the cam chain?



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Old 11-27-2010, 08:48 PM   #16
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Re: Engine Seized - Please Help

Quote:
Originally Posted by PeterSeymour
Clearance between the head and the top tube seems minimal at best so I'm worried I will have to drop the engine in order to get a look at the camshaft. Does anyone know if you can remove the valve cover without removing the engine? Or can I at least lift it up enough to get a look at the cam chain?
The valve cover can be removed with the engine in the bike.(see page 3-9 in the manual,it can be downloaded for free)
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Old 11-27-2010, 11:37 PM   #17
PeterSeymour
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Re: Engine Seized - Please Help

Okay I got the valve cover off just fine like you said and was able to fully examine the cam chain. I think that the chain is actually working fine and that the plastic guide was just slightly out of position - I couldn't actually see that it was broken anywhere so I think I misdiagnosed the problem. The Piston will move freely from top dead center to top dead center so I don't think it is seized, and I am really kind of lost on what it might be. I also removed the generator cover and was not able to see anything out of the ordinary. I have to say I am getting close to throwing in the towel on this, it is just so perplexing as to what it might be. I think I may just try bringing it to a shop now and asking if they can figure out what is wrong. It does sound like there might be a loose or ground gear or something wrong with the crankshaft. I am going to hedge my bets on that but I really just don't know. I am definitely happy that the piston seems at least functional though!
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Old 11-27-2010, 11:54 PM   #18
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Re: Engine Seized - Please Help

I always used a small pry bar to unscrew the cover.A large washer & vise grips will work also,but I always had better luck with the pry bar.If you want to take the whole cover off you need to pull and wiggle the cover to overcome the magnetic pull of the stator.The magnetic pull of the stator can be difficult to overcome.I'm starting to think that your bike may have jumped it's valve timing.This would cause the piston to stop at top dead center because of the valves opening at the wrong time and hitting the top of the piston.when you get the cap loose it wouldn't hurt to check the timing marks,as explained in the valve adjustment section of the manual.
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Old 11-28-2010, 12:00 AM   #19
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Re: Engine Seized - Please Help

Thanks for the tips. I actually managed to get the cover off not two minutes after I posted that. I had been kind of gentle with it but finally a gave it some pretty good tugs. The gasket on that side was actually in horrible shape and had fused the cover to the engine so it came off in strips and pieces. Looks like I am on my way to a full engine rebuild just trying to figure out what is going on. :??:
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Old 11-28-2010, 12:11 AM   #20
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Re: Engine Seized - Please Help

Quote:
Originally Posted by PeterSeymour
The gasket on that side was actually in horrible shape and had fused the cover to the engine so it came off in strips and pieces. :??:
It is normal for the gaskets to get like that with age.Any that I replaced on my 99 were in the same shape when dissembled.I wouldn't give up hope just yet.In case you missed the last part of my last post after I edited it,reread it.
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