replacing seacocks

[simon_sluggett]

without knowing how old the seacocks are on my boat, when is it prudent to fit new skin fittings and valves. Do they have a natural life expectancy or is down to use. What is the best type / material to use. This item may seem like a fit and forget thing , but the consequenses of any failing is pretty dire.

 

[Topcat47]

There's no reason for brass hull fittings to fail in a Glass fibre boat unless there's a problem with the cathodic protection.

If your seacocks are the old "blakes" type (unlikely except for a sea toilet these days) regular servicing wil see them through the centuries, again unless there's a cathodic protection problem.

If they are gate valves.....if they cannot hold water after a service, replace them with ball valves.

If they are ball valves, as long as they operate, leave well enough alone. A smear of teflon grease at refit time is all the servicing they should need. In comparison to the cost of the boat (or gate valves) they are a cheap as chips so replace them when they become difficult to operate.

 

[Poignard]

My boat is 39 years old and still has her original Blakes seacocks. The only one that might need replacing during the next few years is the heads discharge one, which works perfectly but is showing some slight pitting on the cone.

As Mr Rolls, or Mr Royce[?], once said " The best is the cheapest in the end. The quality remains long after the price is forgotten"

 

[srm]

Replaced my cooling water intake at the weekend. Brass or bronze threaded through hull fitting topped by a couple of pipe fittings then a gate valve and a bit of copper pipe to take the flexible hose.
Have had gate valves fail without warning, and not knowing what the through hull was made of I decided that a new Blakes intake was a safer bet.
Removing the old pipe and fitting the new seacock between tides put the pressure on, but got the job done with time to strip down, check and grease the toilet seacocks as well.

Its not only sea cocks that can be dangerous. Last summer I heard a boat requesting assistance as it was taking on water. The problem was a through hull transducer. They had only just left harbour and were safely escorted back in.

As said in a post above, if you have Blakes seacocks regular strip down and inspection + grease is all they will probably need for years. If the cones get worn they can be rebedded with valve grinding paste. Anything else is probably suspect, not least due to the likely mix of metals with different components threaded together and the danger of brass / low grade bronze failing due to de-zincification.

Have fun.

 

[VicS]

Bronze seacocks etc should last for ages and not need cathodic protection(The boat I have been sailing this week is nearly 30 years old, has the original bronze seacocks and no cathodic protection.

Dezincification resistant brass is second best and any other brass will have a very short life without CP. IMHO no brass other than DZR should be used.

Examine the fittings for any pink colouration. That will indicate dezincification and it would be prudent to replace them.