15 years ago
and experience there is out there in this group, so I thought it is
worth asking the question anyway.
I have a small boat in one of the marinas here in Milford Haven, and
my boat (together with several similar other ones in the marina) is
wasting one of her sacrificial anodes at a quite alarming rate. I
beached my boat yesterday to check it after only 6 months from fitting
a new one (on the prop shaft), and found that it was virtually
completely wasted, so I replaced it again. Some of the other boats
with similar protection systems reportedly get through their anodes at
an even faster rate, one owner claiming that he changes his every 3
There is a second sacrificial anode which is wired to the rudder
stock, engine, gear box and fuel system parts which also wastes
quickly, but as this is a much larger lump of metal, will last longer.
The marina is predominantly salt water, swept by the large tidal range
in the haven, although there is a small fresh water stream which flows
into the marina.
Changing the anode is at best awkward and time consuming - waiting for
the right tide at the right time on the right day and having the right
weather to be able to beach the boat, and the owners who have their
boats craned out to do the job face a bill of anything upwards from
=A3150 for the lift.
My question is, does anyone have any experience with impressed current
cathodic protection or any other means of preserving the life of the
sacrificial anode on small boats? (shore power is available in the
I have contacted a number of "professional" corrosion engineers who
will not comment until they have surveyed the location (at a cost
which may be acceptable to oil companies, but not retired boaters!)
and will then not offer any certainty that they can recommend a