In the old days before torque wrenches came into use, the service manuals said to put an open end wrench on the flywheel nut and beat on it until it stopped moving. This left great latitude in how tight the nut was. Some compounded the problem by putting oil on the junction, thinking it would make it easier to take apart. Instead it became easier to FLY apart. It wasn’t until Evinrude started supplying outboards to the Military in the early 1940s that torque numbers were specified for the Speeditwin, Speedifour, and Big Four at 75 to 80 Foot Pounds for their Flywheel nuts.
