XJ will not start, Help

93 XJ, I recently purchased this. The previous owner had pulled the motor out and thought the bearing in the lower end was bad. It was only the flywheel. They reinstalled it. It will not fire. Does have fuel. Changed the crank senor (under the rotor in the distrib), crank position senor on the trans housing. Cranks over fine but does not fire. Owner said dist. was not pulled when motor removed. Help!!