How to get a sea cock unstuck

[andrejsv]

First, I am on the water. No triac, rusted stays, so I dont want to sail it (plus I really dont know how to). So I cant take the boat of the water just yet.

My problem: the raw water seacock for engine cooling is stuck open. I tried closing it but it would not give. It has what looks like a plastic handle so I did not want to use a cheater bar and break it.

All the engine hoses have rusted screws on their clamps and I want to replace them as part of trying to get the engine running again. In order to remove the hose from the sea cock I would have to cut it in half and I'm afraid of sinking the boat.

Is there a trick to unsticking it? or maybe cut the hose, and then make a union to a longer hose and raise it above sea level? and then what?.. use some sort of chemical solution to get the seacock working?

Or is it better to leave the hose as is until I get the boat running (or in worst case towed) and hauled?

Thanking you for any suggestions,

[AnchorageGuy]

The easiest and best way is to haul the boat out of the water, remove the problem, valves, clamps, etc., replace them and then put the boat back in the water.

[Cheechako]

If that is a Black Marelon seacock, they stick terribly if not worked every couple of weeks. The handles are the weak point and will definitely break or fail where the little "cog" tries to turn the ball. I know of no solution in the water to turn the seacock. You should be able to unscrew the clamps though even is rusty? I ussually use a 1/4 drive witha 5/16 socket, although some clamps are a diff size. When you buy new clamps , buy the ones with "316" on the screw housing. It's too bad the Marelon 's have that problem, the material itself is tough as hell. I removed one (broken handle) once out of water and had to literally chisel and saw it into pieces to get it out. Unbreakable... except on handles!

If you need to shut it down before you can haul out, use two pieces of wood to protect the hose, and a set of vice grips. No way to break it loose without chancing breaking it off. If you can dive on the boat, you can put a wood plug in the through hull, but be careful, as it is possible the through hull, if marelon, or plastic, might break with too much pressure. This might not be an option if there is a strainer over the outside through hull. Not really clear what you are trying to do, but rather than try to ge the engine running, unless you have a long way to go to haul out, I would recommend toing the boat to the haul out, and working on it on the hard.

[S/V Illusion]

I think the first order of business here is to identify if, in fact, you have a true seacock or simply a plastic Marelon value on a thruhull. The fix is totally dependent on your answer.

[SilentOption]

Obviously hauling is the answer.

If you can't haul and really want to manipulate the valve handle while you are in the water I would get a DC plug and hammer and go over the side.

Gently tap the DC plug into the thru hull fitting. You don't have to pound on it too hard to make it stay in.

If you are in a yard and hauling could be an option I would then ask if hauling out on short notice is a possibility. Tell them that you are working on a thru hull and might need to be towed to the lift.

Start working on the valve first thing in the morning so you have the entire day(daylight) ahead of you to solve problems that might arise.

With the DC plug in place you can first remove the hose and confirm that the water is not flowing in.

You can evacuate all of the water from the valve and pour some suitable lubricant into the valve. Its doubtful that will free the ball but you never know and once you start wrenching on the valve you will run the risk of breaking it off completely.

Be gentle with the valve and handle. Support the valve as much as possible while pulling the handle. Sideloading the valve could snap everything off right at the hull.

[olepedersen]

wrap seacock in an old towel leave the handle accessible. get lots of boiling water pour over the towel and body of seacock for several minutes to get the body as hot as possible then try to move handle, it worked for me,good luck Ole

[Chief Engineer]

fershure fershure

Originally Posted by olepedersen

wrap seacock in an old towel leave the handle accessible. get lots of boiling water pour over the towel and body of seacock for several minutes to get the body as hot as possible then try to move handle, it worked for me,good luck Ole

[Cheechako]

Learn something every day. I like the hot water idea... just dont get it on the handle which is flimsy enough. I doubt if you can break the Marelon driving the plug in from outside. As I said above, I couldnt break it with a cold chisel.