I have a John Deere with a 23HP Briggs and Stratton V Twin 44L777-0115-B1 that had been running slow and then stopped. After much effort I finally found that the push rods were bent and that is why it will not start. I need to know how to check the timing to assist in trouble shooting. I have also had a time trying to get the flywheel to let loose. Any advice / help would be greatly appreciated.