Engine Sprocket nut stripped

[Wheaton Jr.]

Today I was putting on a new tabbed washer for the engine sprocket nut because it needed to be replaced. I looked up the torque spec. in the Clymer manual and it said it should be 81 ft-lbs. When I was torquing the nut, it all of a sudden got really loose. I stopped, took the nut out and the threads were gone. So I ordered a new nut and before I tighten the new one I want to make sure that you guys also torque that nut to about 81 ft-lbs. I was hoping that the nut's threads were just to blame. Thanks, David.