I was looking at your pictures and here are my comments on them;
1) the metal shavings look like they are from under the transmission gears....is this where you are finding them? If so, it sounds like something broke and was ground up by the gears or, perhaps, you had a bearing fail in the gear train. Take a look at the oil pump screen and see if it is clogged with metal. A clogged screen will cause oil starvation.
2) the oiler for the drive chain is damaged and needs replacing
3) the cam chain slipper (the long black piece) looks like it is damaged and needs replacing. Is metal showing on the face of this slipper......if so, it is definitely worn out.
4) the cam chain tensioner roller and its center bearing holder look normal for an engine with 70K+ miles. If the roller is showing cracking, it needs replacing. If it isn't cracked, you could reuse this part but it depends on what else you do with the engine. If you are doing a total rebuild and spending lots of money on other new parts, then you do want to replace this tensioner roller.
5) if that slipper really is damaged and worn to metal, you probably have a stretched cam chain and the cam chain tensioner (the plunger which pushes on the tensioner roller) may not be working properly. The shop manual tells you how to check these items. Unless you know when the cam chain was last replaced, you should go ahead an replace it.
6) the primary drive and its dampers should be checked. The dampers will shrink, get hard, and crack. They should already be in the hard stage (the engine looks like it has lots of mileage on it). The shop manual gives the specs on this and details how to check it. When you put the assembly together, the fit should be snug. When the dampers shrink too much, the assembly exhibits free play ..... you will be able to wiggle it back and forth.
It is unfortunate the engine was full of metal particles. You are going to have to spend a lot of time inspecting all the gears and bearings with a microscope looking for damage. The crankshaft has an end bearing which slides off and you can look at these bearings. If you see any damage on these bearings, there is a good chance the other bearings are also damaged since they saw the same oil. If the metal shavings are aluminum, the problem is not as serious but if there is iron in the shavings, that can put small scratches on the bearings and while the engine may work fine now, it does cause the engine to start failing and you may not see the effect for 10,000 miles.
If you kept any of the motor oil which was in the engine, you could stick a magnet in it and see if any iron particles attach to it. The better way is to have the oil analyzed for its iron content which gives an immediate indication of how bad things might be. You probably are not interested in getting your oil analyzed but if you do, check the aviation yellow pages. Oil analysis is popular on planes (large and small) because it lets them detect problems well before the engine fails.
See what it needs and then you can determine whether you want to rebuild it or buy a used engine. You may also want to take a class in machine tool operations (learning how to use a lathe, milling machine, surface grinders, etc) so you can make or recondition your own parts.
hope you are learning lots,
Dale
> Thanks
> to someone's nice post about flywheel/rotor removal, and Dale's info about the > internals of the gear box, I have now opened up the engine case. Everything > looked pretty good, except that I had a LOT of metal shavings sitting in the > bottom of the case.
> http://i81.photobucket.com/albums/j228/ ... IM0799.jpg > I > didn't have time to start taking gears out yet, so I haven't found a for-sure > source of all the shredded metal. One possible source is the guide that the > cam chain slides on. Both the cam chain tensioning wheel and the cam guide are > severely eaten up, and the long skinny guide that runs up the length of the > chain is missing a little bit of metal on it. I don't know how much metal it's > missing since I don't know what it looked like originally. But here's a > picture of the guide and the tensioning wheel:
> http://i81.photobucket.com/albums/j228/ ... IM0798.jpg > I > don't know for sure if the guide and wheel are where I'm getting my metal > flakes, but I do know for sure that I'm going to need a new guide and > wheel.
> I've also been finding very interesting parts, the likes of > which I've never seen in any other engine. Like this Drive Sprocket Dampener > thingy ma bobber:
> http://i81.photobucket.com/albums/j228/ ... IM0793.jpg > It's > got these little plastic things inbetween the two drive pieces, I guess to > help reduce vibrations and stuff. Very fascinating. Is this something that > wears out and has to be replaced very often? Mine seams ok to me, but I'm not > totally sure what ok is.
> Also: the little plastic thing that apparently
> sprays oil onto my drive chain is a little bit broken. I might be able to > re-use it, but if a new one is out there, I'd prefer to have it in my > engine:
> http://i81.photobucket.com/albums/j228/ ... IM0800.jpg > Are > regular parts stores, or honda dealerships a good place to go for stuff like > this?? Or is there a secret website where I can find Honda 600 internal engine > parts? Or do I just need to be very careful with my old one, since it's almost > unreplaceable. I've seen some of this stuff on Ebay, but I'd much rather get > new than used.
> thanks very much,
> Mike.