While most people with experience repacking the gland with the boat in the water will tell you how "easy" it is, the first time you do this you need to be prepared with a Plan B if the Law of Unintended Consequences sets in. You may experience a "lot" of water rushing into your boat from the opened gland/log so be sure your blige pump can handle it. I've used the bicycle tube wrap around the shaft/log to control this inflow and it does work. There are lots of variations on this theme. I've found that it may be difficult to remove/pick out ALL of the old packing material and that is a must. I use a pair of small needle nosed pliers and/or 3" dry wall screws to get all the old material out. Finally, repacking with the right size packing material is crucial. You don't really need to know the diameter of your shaft; what you need to know is the exact clearance between the shaft and the inside of the gland compression nut. Don't let anyone tell you what this size is -- measure this critical distance yourself. After you get the gland repacked and compression nut screwed back on, make sure you can turn the shaft by hand to test for the "right" amount of friction. Tighten up your docklines and run the engine in gear @ about 1200 rpms or so while watching the gland to see how much it leaks and readjust the nut as required. What you really care about is how hot the gland gets after running the engine for a while. The nut should be warmish or cool, but not hot. Check the leak rate, and heat, of the gland every time you use the boat until you are confident all is well there.
