Yacht

A rubber bellows replaces the straight length of hose found on the flexible
stuffing box. The watertight seal is formed by a graphite flange that nests
inside the forward end of the bellows with the double solid hose clamps.
Dripless Shaft Seal
This reduces the sensitivity to
misalignment of the shaft but
introduces the possibility of hose
damage or failure allowing water to
flood in. Four hose clamps are
required, two on each end, to secure
the hose. The clamps and their
screws need to be all stainless steel;
bring a magnet along to the ship’s
store to check the screws in particular.
Marine stainless steel alloys are
austenitic and should not be magnetic.
The clamps should also be the
non-perforated type.
In addition to the old-fashioned
stuffing box being too simple and
reliable for the contemporary marine
marketplace, a few other shortcomings
have driven the development of
the dripless shaft seal. This “better
mouse trap” has become more
common in recent years aboard new
boats and for those retrofitting older
vessels. Aside from the obvious claim
inherent in its name, these seals
benefit from not needing packing at all.
A rubber bellows replaces the straight
length of hose found on the flexible
stuffing box. It, too is clamped to the
stern tube at the propeller end of the
shaft. The watertight seal is formed
by a graphite flange that nests inside
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