Skin fitting/seacock replacement - an update

[IslandAlchemy]

Just got the old one out today and thought some of you might be interested in what I found.

The boat is a 2003 and these are the originals, so they've done 17 years, half in the Caribbean and half in the UK.

Comments not in any particular order:-

1./ All the small toilet inlet seacocks and skin fittings unscrewed with no problems.  All the big toilet outlet ones needed grinding off.

2./ All of the skin fittings were still in good shape and nice yellow brass colour all the way through.

3./ All of the seacocks were in reasonable condition with no signs of de-zinctification.

4. ALL of the hose tails were in a mess.  The barbs all broke up tryin to get the hoses off. One of the small ones snapped off at the barb end whilst trying to remove the hose, and one of the big ones snapped off whilst being hit with a hammer to loosen it.

So they were well due for replacing, but I was surprised that in all cases it was the hose tails which had gone rather than the skin fittings.

[Nicho]

Interesting, thanks for the info.

[Symphony]

Dezincification of the tail is common because seawater sits in the junction between the hose and the hosetail nipple which has a chamfer on the end of it. Once the barb starts to breakdown water creeps between the hose and the fitting. This does not cause leaks and goes unnoticed. The fitting becomes weak because it is then crumbly copper, although as it is under no strain is unlikely to fail until you hit it or try to remove the hose. The other common place for dezincification to start is behind the flange of the skin fitting if the sealant or gasket breaks down.