Shaft Packing; how long should it last?

[NorthernFocus]

In my youth I worked on various commercial vessels and charter yachts. Back then packing was made out of flax impregnated with wax. Adjusting/tightening packing was a routine task. And if it didn't wear out it rotted. SOP was to replace packing at the start of every season. My how things have changed with modern materials. We bought our 2008/9 R25 Classic used and replaced packing/aligned engine during commissioning for the 2015 season. I used teflon packing material. Last week after over 2200 operating hours I finally had to tighten it. After ten years I should probably replace the packing on GP but I'm a cheap old fart.

 

[zzr7ky]

Wondering myself...for the same reasons.
I do attempt to see what leak rate i have. Also with limited success. I end up standing around the sandbags, shooting the breeze with others, and deciding that the pump doesn't kick on at all often, so it's still good!

 

[Cutwater28GG]

touch wood...going on 10 years.