Ok. New issue recently discovered. At some point since this issue started the crankshaft sprocket stripped out and has been spinning freely on the spindle. As a consequence, every time I've tried to start the car for the last day the cams have not been turning when the crankshaft turns. I've found a new crankshaft sprocket, but am hesitant to spend the money because I'm concerned that the crank spinning while the cams are stationary has ruined valves. What do you think? Is it likely that i've ruined something, or is it worth spending $100 on a new sprocket?

The timing marks looked dead on to me. but I have ever heard of the crank sprocket stripping before. If this happened when you were driving, then there was definitely contact between valves and pistons, but if it happened only when you were trying to start it then it is possible that there was some minor contact between valves and pistons. Did you hear any strange noises or did the motor act like it was binding a bit when you tried to start it? if so, then there may have been contact. At the very least you are going to have to take the timing belt off and retime it properly, finding top dead center on cylinder number one. If there is only one way that the crankshaft sprocket can go on then timing it should not be too hard an issue as the mark on the sprocket should be where it needs to be. Check the front of the crank and make sure nothing is cracked or sheared off before you put on new sprocket. If you do put on a new sprocket and get the timing marks lined up, make SURE that once you get it together you put a wrench on the crankshaft pulley bolt and turn the engine over by hand through at least 4 full revolutions of the crankshaft to make sure nothing is binding. If you feel any binding (outside of the normal compression) stop as it is not timed properly. If you can turn it through 4 full revolutions by hand with no binding, it should be ok to try starting it with the starter

The inside of the crank sprocket looks almost identical to this one, the difference on mine from this one is that the teeth on the spindle are not smoothed over.

https://volvoforums.com/forum/volvo-...ng-gear-89394/

If the sprocket is fully seated onto the spindle then it seems to tie in, but if it slips off even a couple millimeters it is able to spin freely on the spindle. I have a suspicion that a previous owner discovered this failing part and patched it together just well enough to get rid of the car. I heard something that may have been interference between valves and pistons the last time I tried to start it, and possible binding but I can't say for sure because the battery was pretty drained and it could have just been that there wasn't enough power to continue cranking it.

I'm pretty sure the car is done, I might pick up another sprocket, it looks like a used one can be had for around $30.

Thank you so much for trying to help me. I really appreciate it.

No problem, glad to help in what way I could. If you decide to keep working on it, just post here on the forum, I will keep an eye open. Good luck with whatever you decide.