Removing old seacocks.

Ship's Cat 73

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We have 2 old gate valve seacocks we want to replace.
One of them is fitted with a strainer (similar to photo).
I'm assuming (due to age - mine as well as the boat!) that I won't be able to undo the securing nut inside so I'm expecting to be using the angle grinder.
How easy will it be to cut through that strainer? . . . or is there an easier/better way to do this?
Strainer.jpg
 

Tranona

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Quite a chunky bit of bronze so could be hard work. Easier to cut the nut off maybe depending on access. those strainers are out of fashion now since the advent of above waterline strainers.
 

andsarkit

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Try the nut first and if it won't move you can split it with a Dremel and/or cold chisel.
If you drill a hole in the side of the strainer you might be able to rotate it with a long strong bar if it won't push/hammer/lever out. It all depends on the type of sealant used as Sikaflex can be a tough adhesive.
 

Never Grumble

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Depending on size, the strainer part is probably not that thick so I'd be inclined to cut the scoop off with a grinder and then use a step drill from the outside. Never done one but have got one to do ... next year so let us know how you get on. Mine is for the heads inlet.
 

bignick

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On my old seacocks I managed to undo the nut a couple of turns, then it didn’t go any further. That allowed me just enough space to pull the seacock outboard a few mm and use a multi tool fitted with a steel cutting blade to cut through the threaded shaft. Came off in no time with very little mess and no angle grinder dust. I did a strainer like the one your photo that way too.

PS - If you do them that way you don’t need to bother removing the hose tails etc on the inside first - you can just cut the hose (assuming you’re going to replace them anyway), which saves even more time and messing.
 

KLBH

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I replaced all our sea cocks by using a small angle grinder, for the strainer grind off the "legs" of the strainer then treat it the same as a standard through hull. That is to carefully grind away the inner wall of the through hull tube as it goes through the hull. You will probably manage to grind away about 80% of the thickness, then you can break off the outer section (making sure you use an old scrapper or something to protect the hull).
Sorry my description is not great, but it works well and grinds away easily.
 

mattonthesea

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As above, my first time using an angle grinder. Quick practice and then for real. Two mins to remove grating and then five careful mins to take the lip off. Tapped the shaft out with a socket and all done.

Trudesign in a few minutes later after cleaning up.
 

lustyd

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Get some stilsons on it. Angle grinder should be an absolute last resort - it's slow, messy and causes a lot of heat where you don't want it (your hull!).
 
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