Turns out it was the crankshaft

 

Did it fail on you, or do you have any idea what happened, or whats about to happen?

 

Not sure exactly what happened. I had a mechanic look at it and he told me the crankshaft is busted and it wasn't worth rebuilding. Although I'm pretty sure the engine was installed wrong by him so I'm just going to drop a new one in there myself this time or put a new crankshaft in the current engine. So I guess my next question is should replace the crankshaft in the existing one or just put a new engine in? I haven't got a good chance to look over the existing to see what other kind of damage was done when it broke

 

Put your mind at ease and put in a new engine. If you just replace the crank in the exisiting one, you will likely always wonder if its gonna last or if its integrity has been compromised. Trust me, it will drive you nuts......

 

Yeah I figure it'd probly be easier just to drop a new one in rather than having to open up the old one

 

Good choice!