This happened after replacing the timing belt and intermediate shaft seal. First time doing this. (1982 245 ~145k) Removed fan and shroud, then accessory belts, futzing around with the AC belt before discovering the split crank pulley. Removed the cover, set back tensioner pulley and removed gears to inspect for cracks and get a look at the seals, since something was leaking. (Used "the rope trick" (Don Foster, 1999) to get the crank pulley off, which seemed to work well.) Decided the intermediate shaft seal was the culprit; replaced it. Now returned all gears, again using the rope trick (in reverse) to replace the crank gear. Took some time to get the belt on, but double and triple checked alignments before loosening the tensioner pulley and beginning reassembly. Unfortunately, discovered the inner guide plate left off after beginning reassembly, so repeated the whole process to install it behind the crank gear. Being Sunday, left off installing the belts til today, so I could get new ones from the parts house. Put the belts on, fired it up. Ran for a few seconds making a "rattling" noise. Either it quit or I shut it off; I'm too disgusted to remember, but upon cranking it again, it spun too freely, like no compression. I assumed somehow the belt had slipped (but how?...) After disassemby and checking the timing marks again, I discovered the crank gear out of position, between 2 and 3 o'clock . Upon closer inspection and removal-it was broken; key sheared off and split in half. Now I am completely discouraged. What have I wrought? Have I wrecked the engine? Suggestions?...Help?...