C O M M E R C I A L LY R AT E D
WAT E R M A K E R S t o 5 5 0 l / h
This system produces 250l/h, with
2.2kW motor and SS Cat pump.
VIP.S94
Now available from NZ
distributor
So-Pac Marine.
www.skipper.co.nz
O I LY W AT E R
S E PA R AT O R S
www.sopac.co.nz | info@sopac.co.nz
+64 9 448 5900 | 41c William Pickering Dr, Albany, Auckland
VIP.S93
another well known brand was having failures when the vessel was
only two years old.
We had not had our through-hull fittings bonded and the one zinc
anode on the shaft showed a moderate degradation over a 12 month
period. Another yacht, like us, did not have fittings bonded at first,
and after experiencing some failures had them all bonded – but the
electrolysis problems continued.
With all the variables involved it does seem that it cannot be
an exact science to cure this problem and it's one that is hard
to beat. I am sure that there some experts out there who will
disagree, but over the years I have found that each vessel has its
own "electrolytic" personality, dependent upon the makeup of the
through-hull fittings, whether they are bonded or not, what they
are bonded to, electrical leakages, the hull itself, where the vessel
is berthed, if there are any electrical leakages from the marina's
system, and what, if any, electrical leakages may be coming from
other vessels close by. Now, try and make up a formula that will
cover all those possibilities and more, that will successfully keep
electrolysis on your boat under control.
It certainly seems that the electrolysis problem can be minimised
and, apart from having your boat wired and earthed correctly,
sacrificial zinc anodes are a good first line of defence and
generally an indicator as to how things are going in the electrolysis
department. Still, even after keeping an eye on our one anode,
which was deteriorating slowly, and regularly checking all metal
through-hull fittings, I was still caught out.
So, what's the answer? I am certainly no expert, but for many
years I have carried out the following procedures, and although not
being very technical, they have kept me afloat:
Regular checks on all through-hull fittings, especially metal
ones, are essential, but if you are going to test them with a light
tap from a hammer, make sure there is an appropriately sized plug
ready to insert.
Keep a good check on the boat's sacrificial anodes, although, as
already mentioned, they are only a possible indicator and part of
the answer.
If berthed in a marina, avoid having shore power continuously
plugged into your on board system, and switch off your house and
start battery banks when not in use, if the boat can survive without
having them on.
Those boats on a swing mooring, or that spend a lot of time
cruising, usually have fewer problems with electrolysis than those
in marinas.
Otherwise, take the boat out of the electrolyte and keep her on a
hard stand and start up "Hard Stand Charters". Or you could
sell the boat and buy a caravan, but where's the fun in that?
July/August 2013 Professional Skipper 39
