I recently purchased this item for my Husqvarna model 455 chainsaw (Order# 3367816). The service manual for the Model 455 stated the torque value for this flywheel nut is 25-30 Nm or 18-22 ft-lbs. When I reached about 14 ft-lbs the threads stripped right out of the Nut. So my question is what is the correct torque value for this Nut ? or is there something wrong with the hardness in the metal that the Nut is made from ?