Re-pack stuffing box - How often?

[dmalcol1]

I had pss shaft seal fail after two years turns out boot does not like diesel. The repower of vessel went well but for couple of months there was a persistant small diesel drip at return line. The shaft seal boot swelled and failed. When boat was hauled replaced with oversized diameter boot that allowed old stuffing nut to live loosely in side of boot. failer of boot would now require the boot to be cut open and stuffing seal nut tightened. Probably would not replace dripless boot again.

[David Mathis]

After having several boats with stuffing boxes but now having dripless, I tends to prefer the minor annoyance of the slow drip. The dripless were wonderful until about a foot of water in the bilge was traced to a chipped seal. Although no one would admit to causing the problem, the logical assumption was that one of the mechanics onboard the previous week dropped a tool which struck the seal. The boat had to be hauled, shaft coupling removed, and the shaft slid back before the $500.00 seal was replaced. Replacing packing is much simpler, much cheaper, and can be done in the water if you have fast hands although the recommendation is usually against it.

As to how often to replace the stuffing? If you can still adjust it, it's likely still fine. I haven't tried the grease method mentioned in this forum but it's a logical approach to an old problem.