Ball valve seacock leaks when closed

[webcraft]

When I took the heads outlet hose off for percussive refurbishment yesterday there was a substantial trickle of water from the seacock when it was apparently tightly closed. I had to put a bung in while the hose was off.

Is there anything I can do with the boat in the water to try to fix this? (I have repeatedly opened and closed it).

It is obviously not an emergency, as there is a double-clipped hose attached that rises above the waterline, so I will leave replacement until next haulout. Howwever, I am curious as to the cause. Valve was fitted by me 4 years ago, DZR.

- W

 

[michael_w]

Marine growth scoring the plastic seals?

 

[James_Calvert]

Loving and recognise "percussive maintenance" on that hose!

Had you ever had reason to test the seacock previously?

 

[Boater Sam]

Duff valve. Replace. You should be able to snatch change it in the water.

 

[Stemar]

Duff valve. Replace. You should be able to snatch change it in the water.

I had a mate who would do that. I was never quite brave enough!

 

[Minerva]

How far below the water line is it? Could you fit a bung in from the outside to allow you to change the valve?

Or could you fit a new, second valve in series just now and then in the winter when hauled out remove the shonky one and re-fit the new and good one?

 

[webcraft]

Duff valve. Replace. You should be able to snatch change it in the water.

A recipe for disaster. There is no danger in leaving it until next haulout.

 

[webcraft]

How far below the water line is it? Could you fit a bung in from the outside to allow you to change the valve?

Or could you fit a new, second valve in series just now and then in the winter when hauled out remove the shonky one and re-fit the new and good one?

No space for 2nd valve, and major structural work (heads floor up) required to change.

 

[webcraft]

Loving and recognise "percussive maintenance" on that hose!

Had you ever had reason to test the seacock previously?

Never tested it previously, could have been faulty from new.

 

[Minerva]

Ok, how about;

If it's a ball valve and leaking, it stands to reason there is a foreign object (my bet is mollusc) in the valve. Could you open the valve with no pipe attached and give the aperture a quick going over with a half round file? See if that dislodges it?

 

[webcraft]

Ok, how about;

If it's a ball valve and leaking, it stands to reason there is a foreign object (my bet is mollusc) in the valve. Could you open the valve with no pipe attached and give the aperture a quick going over with a half round file? See if that dislodges it?

I did give it a quick rummle from the outside with a screwdriver yesterday, but it made no difference. Might have another go another day from the water. No need to take the pipe off if done from in the water?

(or am I misunderstanding you?)

— W

 

[Minerva]

my thinking was when I change my log paddlewheel transducer at the end of a sail, I can see a perfect blue circle through the thruhull when there is an inrush of water. If the same were to apply for your seacock then you might be able to see where a wee barnacle was hiding and knock it off...

 

[ean_p]

If the valve was indeed fully closed then it would suggest that both seats and or the ball are badly damaged / pitted/ deformed / worn / encrusted. As the valve in effect has two seals then for it to leak suggests that the valve is in a poor state internally. Are you sure the valve was fully closed as just a few degrees away from its 90* rotation will expose a leak path either through or around the ball !

 

[Dipper]

Can you fit a short length of hose to the valve so that the hose end is just above water level? You can then inspect the valve (open and closed) by looking down the hose without any risk of letting water into the boat.

 

[2Tizwoz]

Put some vinegar into it and let it sit for a day. Should remove crusty bits.

 

[Laysula]

Leave it till your next lifted out. Not much chance of getting the valve off without disturbing the skin fitting. If you do that then your in a lot more trouble.

 

[Stingo]

@webcraft , just checking up on you? Have you sunk yet?