Stuffing box opened up

Within the compression nut at right are several strips of wax-impregnated flax packing. When the nut is tightened down on the packing gland body at left, the packing squeezes against the shaft, forming a nearly water-tight seal. Once the correct degree of compression is achieved, the compression nut is prevented from turning by the lock-nut.

Setting the correct compression can be done by hand but securing the lock-nut requires two 1 3/4" wrenches. The lock-nut must be secure to avoid the risk that the compression nut will loosen and come off, which would sink the boat.