checking seacocks for leaks on the hard?

[wayneA]

After sailing other peoples boats for 18 years, I'm now buying my first yacht. She is out of the water at the moment and will be on the hard for some work to be done before relaunch. One of the tasks will be servicing all the seacocks.

So how do I check the seacocks for leaks etc, whilst out of the water? I don't want to put her in - find leaks and then (I think?) have to haul her out again to fit a new one.

Any advice will be gratefully received.

TIA

Wayne

 

[vyv_cox]

You can check ball valves in reverse, by putting water in sinks, attaching hoses, etc., as appropriate. This is not the same thing as checking with the pressure in the correct direction but it's probably good enough. Otherwise you might want to take them off to check from the correct direction, but I would not bother.

If you have any gate valves, bin them now.

Plug valves are very reliable. Take them apart and clean the mating surfaces, then put a small dab of grease on the cone and put the valve back together. Rotate the plug a few times then pull it out and inspect. The grease should have spread over the whole surface. If the valve is worn there will be an area in the middle that has a "waist" and this will be dry. In this case, use valve grinding paste from your local car parts shop to re-bed the valve, tightening the bolts as needed to keep cutting.

Bear in mind that a slight leak from a seacock is rarely fatal. Some people never close them and their boats don't often sink. Hoses don't fall off seacocks of their own accord. Only if a leak will let water directly into the boat should you make strenuous efforts to test them.

 

[WayneS]

Similar name, had a similar problem.

I bought a boat that had been on the hard for a number of years as well. I took the attitude that if the seacock did not look like it had been replaced in the last few years, I replaced it before launch. For the sake of a couple of quid....... I suppose that it does depend on how many that you have got though. I only had to contend with 6.

If they are easily removable, take the whole thing off, have a good look at the inside, clean up the threads on it as well as the skin fitting, give the insides a bit of lubrication and replace (With some PTFE tape)

Should not take you more than 20 min per itme and it is well worth it.

As I said before, if in doubt, replace it.

Best of luck and welcome to the board.

Regards

Wayne

 

[boatone]

Would second all this with one very important addition....dont just service the seacocks but also check the skin fittings very carefully. Its not a big job to replace them completely if at all doubtful and then you will know all is ok.
( I recently returned a boat to the water only to have it immediately relifted because of internally corroded skin fittings leaking! Believe me, its a lot cheaper and less nerve racking to fit new ones!)


TonyR
boatone@boatsontheweb.com
www.boatsonthethames.co.uk

 

[mick]

Vyv,
I take it the plug valve you refer to is a Blakes type seacock. Is there a special procedure for tightening down this type of fitting? Either I screw them down tight and can hardly move the damn things or they are easy to operate but the top plate is slightly loose. Advice would be appreciated.

 

[vyv_cox]

Yes, Blakes seacocks are plug valves in my (hydrocarbons equipment) parlance. I do the same as you, tighten by fingers until the handle stiffness begins to increase and then tighten the lock nuts. If Blakes were prepared to move slightly more out of the 19th Century and use metric threads, or even a fine Imperial would not be too bad, this job would be much easier. The current threads (Whitworth?) are far too coarse for a fine adjustment and these are the only fasteners on the whole boat for which I have to keep AF spanners.