Well, the YLwagon has done its duty as far as I am concerned, after us owning it since 1998. What started as a water pump change, progressed to include the timing belt service, new spark plugs, VC gaskets, and so forth. AndreasPassat helped me get the thing into service position, and also inspected the cam chain tensioner pads while he was at it. After many hours of needlessly cleaning parts and even waxing the crank pulley, the new timing belt and rollers were on, and after two crank revolutions, the timing marks were perfect.
It started, then quit after a second. The next cranking didn't sound right. I removed the upper belt cover; to my surprise the belt was still tight, so I figured that something failed, faulty belt teeth perhaps, or the crank sprocket key sheared. I tried to rotate the crank, but found that it turned easy until hitting something.
I let it sit a couple of weeks, convinced there must be bent valves, then the other night I removed the crank pulley and lower cover for a look. The belt was still intact and perfect. So I turned the crank with a ratchet wrench, and felt the interference again, but after a couple of times rotating back and forth, the crank went around normally, and the timing marks still lined up. I also pulled the valve cover, looking for something wrong under there, but all the valve followers moved normally and the chain was nice and snug.
Cutting to the chase, I cranked the engine with the starter (no plugs), and the cams rotated fine. So I put the plugs in (no coils), and cranked again. This time the cranking speed slowed down within a few seconds. The battery was still fully charged- but now I can't move the crank at all with the socket; something is seized. I don't know if seizure is in the engine, or transmission, but at this point, I'm done! Fortunately, the stable-mate Audis are OK.