Sea Cock problem

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BlueSkyNick

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last evening, I went to clean the sea water strainer into the engine, turning the sea cock off first. Its the type which is brass cylinder about 8" high, 1.5" dia. The plate on top is held on with two wing nuts, which I removed to pull the cylindrical filter out.

As soon as I slackened the wing nuts, water came squirting out under the plate which I thought was just a little leakage. When it kept coming after a couple of seconds, I realised the sea cock hadnt actually shut off, so I checked the lever had turned through 90degs which it had.

Beggar!! The lever is moving but the sea cock is not closing. Whipped the filter out quick, with one hand holding the water in, pulled out all the weed, popped it back in, and put the plate back on quick.

so it seems like time for a new sea cock. I am planning to continue using the boat until I can arrange/afford a quick lift and fix. There are obvoiusly risks to this, but I am comfortable I can manage them - the hose is in very good condition, the impellor cover is well and truly watertight and there are plenty of wooden bungs are to hand!

Might there be a quick fix, eg maybe the handle is spinning on the shaft which can be easily fixed with the boat in the water.
 
Sounds as though you have a ball valve rather than a cone type seacock and possibly just the handle that's gone.

Maybe you can undo the handle retaining nut and get a new handle from a decent plumber's merchant if thats all the trouble is.

In the mean time you may be able to shut and open the valve with a small adjustable spanner. The ball will probably go round and round without the handle so you may want to mark it in some way so that you know when it's open and when it is closed.

When you refit te handle take care you don't fit it so that the valve is open when you think its closed and vice verse.

If the square on the shaft has gone then it will have to be a new valve I guess.
 
The 90° turn jobbies normally have a keyed spindle - worth checking that the handle hasn't mangled ... I tried removing the handle off our heads seacock and ended up breaking the handle - had to replace the whole lot - but we were out of the water already so no big problem ...

Is the seacock integral to the strainer? If not, could you plumb in a temporary seacock inline - big bodge though ... and as you say - currently low risk as is.

If it is clean, then you could put a bung in the underside and replace the seacock whilst afloat .... obvious problem would be the skin fitting twisting ...
 
Nick,
When you do change it, I suggest you also change the hose spout (if that's what it's called) as mine was very brittle.
No obvious de-zincing but when I used it as a lever to undo the ball valve, it shattered. That sounds a bit dramatic: the side of the hose connector broke off - that's a bit better!

I only changed the valve as it looked original (1988) and was quite stiff to operate.. Better than afloat, tho'!

I have had a loo outlet valve fail as you have described - that cost me a lift out mid season! Why didn't Moodys spend a bit more and fit proper sea cocks?

Cheers
 
[ QUOTE ]
hose spout

[/ QUOTE ] <span style="color:white"> .................................................... </span> hose tail!
 
I had a similar problem last year only mine stuck closed. As it was late August I used the sea water inlet for the heads to effect a temporary repair and fitted a new valve during the winter. Like yours, both the handle and shaft turned through 90 degrees and it felt as if it was operating, only when I noticed no water coming out of the exhaust did I know summat was up. I was told it is not uncommon for the weld between the shaft and the ball to go.
 
dont want to worry you too much BUT, some of the ball valves have a slot in the ball, something like a large flat screwdriver slot, the shaft that the handle is on is a shaft with a flat blade on the end which engages in the slot, what happens when you lean on the handle and it goes slack is that the blade has either twisted/distorted and is just not "driving" the ball OR more dangerous is that the shaft has broken and the blade come off, in that case there is nothing to stop the shaft and handle coming out and then the water getting past the ball and coming out of the shaft hole!
 
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