Alan, thanks for the response.
The movement is pretty minimal and difficult to quantify, but I assumed largely lateral. I had not noticed anything previously. If you can get a response from Nauticat that would be good
Do we assume there is some packing material in the ‘gland’ that can wear?
Interestingly I renewed the stern gland packing this year. It was the first time it had been done since new, after 1050 engine hours. Over the years I had tightened up the big nut a few times when the water drip seemed to be excessive and I thought the packing must need replacing.
What surprised me was that there seemed to be virtually no wear on the packing. When undone the packing stuck out and when I tried to screw it back up without doing anything else it was quite difficult. I then extracted the first ring of packing which was basically all intact with a bit of wear on the front surface. I estimated there could only be one other ring of packing inside the nut and I decided not the disturb that. I then put in one new packing ring and re-assembled it all.
I was quite surprised about all this because I had researched extensively about doing the job and had expected to find minimal packing left and that the nut should have about 3 rings of packing.
Any comments gratefully received