I don't know how to tell you this nicely, but why in the world are you spending a dime on that engine if it has a bent crank? It is totalled, using car-lingo.
Throw a Harbor Freight Predator engine on that mower deck and get back to mowing! You're going to end up spending enough to buy one of those HF engines just to tell you why your bent-crank motor won't run.
Well, it ran for three years that way. It's a $500 mower. Maybe it'll run for three more, if the problem turns out not to be the crank. The guy looking at it is only charging me $15 for the check. I can handle that.
A Harbor Freight engine does sound like a good option, though. Thanks.