Seacock threads.

[Allan]

We have a brass seacock that I'm going to be changing in a couple of weeks. It's on the engine raw water. Above the valve is a filter with a threaded lid. At present, if I need to remove the lid, the whole thing turns. When I change the valve I'd like to use some type of thread sealant that hardens enough to stop this happening.
We've had the skin fitting block a few times, it's simple enough to clear quickly but can be a little stressful in confined spaces so minimising problems is the key.
Allan

 

[Tranona]

We have a brass seacock that I'm going to be changing in a couple of weeks. It's on the engine raw water. Above the valve is a filter with a threaded lid. At present, if I need to remove the lid, the whole thing turns. When I change the valve I'd like to use some type of thread sealant that hardens enough to stop this happening.
We've had the skin fitting block a few times, it's simple enough to clear quickly but can be a little stressful in confined spaces so minimising problems is the key.
Allan

It will be BSP. If you are changing the seacock that style is not commonly used nowadays partly for the reason you mention. More common now is to use a DZR or composite ball valve and an above the waterline filter such as this. force4.co.uk/item/Vetus/Type-330-Water-Strainer/T9W If you can mount it directly above the intake you can rod straight down without any concern about water getting into the boat.

If you retain the existing type doubt you will be able to stop it turning when you remove the top unless you use a lock nut.

BTW doubt the existing will be brass. More likely all bronze, but rare now because of cost and the arguably superior arrangement described.

 

[pete]

I think on my Hunter Horizon they had used epoxy resin on the seacock threads from the factory, It came undone without much of a problem when I changed the valve by applying a bit of heat.
In your case I would fabricate a bracket to clamp from the strainer to the hull, web, or bulkhead if possible to stop it's tendency to turn when the top is removed.

 

[Allan]

Many thanks for all the comments. A bracket seems to be the best answer, there's a simple place to put a bracket.
Allan

 

[Poignard]

I agree with Tranona's suggestions (post #2)

1. Keep the existing strainer and prevent it from tuning with a locknut;

or, better

2. Retain the existing seacock (if it is in good order) and fit a Vetus, or similar, strainer level with the water line.

 

[Allan]

I agree with Tranona's suggestions (post #2)

1. Keep the existing strainer and prevent it from tuning with a locknut;

or, better

2. Retain the existing seacock (if it is in good order) and fit a Vetus, or similar, strainer level with the water line.

Many thanks, given the position of the hull fitting it's not possible to fit a Vetus and still be able to clear a blockage without removing the hose. The whole reason for starting this is to change the seacock. As I said above, a small polyprop bracket to stop the filter rotating is a simple answer.
Allan

 

[Plum]

I agree with Tranona's suggestions (post #2)

1. Keep the existing strainer and prevent it from tuning with a locknut;

or, better

2. Retain the existing seacock (if it is in good order) and fit a Vetus, or similar, strainer level with the water line.

Yes, agree.