Seacock seizing up

[chrisharris]

Our two engine intake seacocks have been getting more and more difficult to operate, to the point that I am now not convinced they are actually fully closing. Does anyone know the way these tend to fail? I guess crud between the rotating ball and housing, or potentially around the shaft attached to the operating handle?

I suppose the main question is whether it is worth some more bilge time working them open and closed, or is this likely to damage further? Any suggestions for freeing off? Can they be repaired? I doubt it but worth a thought! The seacocks I am referring to have a handle that operates approx 90 degree arc, rather than the gate valve type.

Many thanks!

 

[Morpheous]

Sounds like you've visited by barnacle bill! I had a similar thing recently until something internally snapped, I could still operate the seacock but it was stuck shut. I had to lift out and replace. Mine was for the toilet though, not engine. Apparently they can be greased if caught in time, but it didn't help mine. Having said that changing it was not as tricky as I was expecting.

Good luck!

 

[LittleShip]

Our two engine intake seacocks have been getting more and more difficult to operate, to the point that I am now not convinced they are actually fully closing. Does anyone know the way these tend to fail? I guess crud between the rotating ball and housing, or potentially around the shaft attached to the operating handle?

I suppose the main question is whether it is worth some more bilge time working them open and closed, or is this likely to damage further? Any suggestions for freeing off? Can they be repaired? I doubt it but worth a thought! The seacocks I am referring to have a handle that operates approx 90 degree arc, rather than the gate valve type.

Many thanks!

What type of seacock are we talking about, some have a grease point that can be removed so that grease can be injected. Some are as you said a ball inside and others are a tapered fitting similar to a gas control cock.

A photo would help

Tom

 

[Tranona]

Ball valves cannot be greased - the ball runs in a composite bearing, usually PTFE. Stiffness is usually caused by a build up of crud in the outlet which can be avoided by regularly operating them. I have just removed a water intake that was in for 17 years, in the water 11 months a year and it was still working pefectly (needed to fit a larger size because of engine change).

The weakness of the design is the handles. They are usually mild steel and corrode so can snap off the spindle. There is also packing where the spindle goes through the body which can cause stiffness if not operated regularly.

Best thing to do is to wait till the boat is out, clean the outlet from the outside. Use a long lever - a big box spanner perhaps on the lever and work it backwards and forwards until it works freely again. If there are signs of leakage or it is really seized, replacement is straightforward, but make sure you get DZR body and not brass valves as sold by plumbers merchants for water or fuel use.

 

[DAKA]

Our two engine intake seacocks have been getting more and more difficult to operate, to the point that I am now not convinced they are actually fully closing. Does anyone know the way these tend to fail? I guess crud between the rotating ball and housing, or potentially around the shaft attached to the operating handle?

I suppose the main question is whether it is worth some more bilge time working them open and closed, or is this likely to damage further? Any suggestions for freeing off? Can they be repaired? I doubt it but worth a thought! The seacocks I am referring to have a handle that operates approx 90 degree arc, rather than the gate valve type.

Many thanks!

Sea cocks in engine bays can expand and seize up due to the engine heat.
Once they cool down they are easy to open/close again.
If anyone has this issue then you need to close the seacock as soon as you stop or wait 5 hours to cool down or start the engine for two minutes on tick over to allow cold water to cool so you can close them immediately before they heat up again.

 

[tangerine]

Sorry to but in here,but while we are on the subject of sea cocks,is it normal to turn them off when moored up in port.

 

[Firefly625]

Sorry to but in here,but while we are on the subject of sea cocks,is it normal to turn them off when moored up in port.

I always do... why wouldn't you? If you have a hose failure and open seacocks you would find your boat full of water.....however I do hang my engine key on my engine seacock to ensure I don't go anywhere without opening it!


....and as this thread is suggesting, regular use is good for seacocks

 

[stelican]

Our two engine intake seacocks have been getting more and more difficult to operate, to the point that I am now not convinced they are actually fully closing. Does anyone know the way these tend to fail? I guess crud between the rotating ball and housing, or potentially around the shaft attached to the operating handle?

I suppose the main question is whether it is worth some more bilge time working them open and closed, or is this likely to damage further? Any suggestions for freeing off? Can they be repaired? I doubt it but worth a thought! The seacocks I am referring to have a handle that operates approx 90 degree arc, rather than the gate valve type.

Many thanks!

I have successfully cleaned off the build up with hydrochloric acid (brick cleaner) bung up the outlet and pore in from the top leave for a couple of hours

 

[blueglass]

I always do... why wouldn't you? If you have a hose failure and open seacocks you would find your boat full of water.....however I do hang my engine key on my engine seacock to ensure I don't go anywhere without opening it!


....and as this thread is suggesting, regular use is good for seacocks

agree in principle but I have no less than 13 of them some in v. awkward places (toilets engines, genset, deckwash etc) its half an hour's work to do them all! So they stay open until I go back home. I know some people who leave them open for the season. (wouldn't be happy with that myself)

 

[Firefly625]

agree in principle but I have no less than 13 of them some in v. awkward places (toilets engines, genset, deckwash etc) its half an hour's work to do them all! So they stay open until I go back home. I know some people who leave them open for the season. (wouldn't be happy with that myself)

mmm... the larger the boat, the bigger the problems... I feel for you

 

[splosh]

Seacocks will seize up with scale if you don't use them regularly. It is prudent practice to use them: i.e shut them to off when you leave the boat every time. This way they will not seize - unless you do not use your boat a lot and the questions on this forum would then be a majority of "how to open a seized seacock"?. A seacock is not really going to seize in the closed position as the elements for scale / barnacles has been "CLOSED" to build up.
Your seacocks are seized / tight due to lack of use.
Every time I leave the boat the seacocks are OFF, unless I am overnighting on charter.

 

[Morpheous]

Without meaning to start a sunseeker thread mine seized and failed when it was shut! When I say failed, it felt as if ithad come free because I could then move the handle, but whatever the handle is connected to snapped so it wouldn't open the valve. Lucky I only had a wee.