How to remove Blakes seacocks

[Jokani]

They have lasted 40 years, but now need replacing.

After a struggle, I have the four nuts from each seacock, but neither seacock will budge, not even being heavy handed with a hammer.

Before I take a blow torch to them, I thought it better to ask for some advice first.

I would also like to replace with Marelon, would I be able to use the existing backing plate (if I do not set fire to it)?

 

[PaulRainbow]

I think you need a bigger hammer Gary

 

[VicS]

They have lasted 40 years, but now need replacing.

After a struggle, I have the four nuts from each seacock, but neither seacock will budge, not even being heavy handed with a hammer.

Before I take a blow torch to them, I thought it better to ask for some advice first.

I would also like to replace with Marelon, would I be able to use the existing backing plate (if I do not set fire to it)?

More brute force an more ignorance called for !


If you are going to fit Marelon see the video on The Forespar website

But also check out Tru Design valves and fittings. They might just be more convenient than Marelon as replacements for Blakes seacocks

http://www.trudesignplastics.com/marine/products

.

 

[LittleSister]

Why do they need replacing?

 

[thesaintlyone]

Had the same problem with mine. Use a heat gun (£10 in screwfix if you haven't got one) Heat the Blakes Seacock inside the boat to help break up the crud then go outside with a wooden pole and big hammer and hit harder than you think. Then they will eventually let go and pop inside the boat.

I presume that when removing the screws you also removed the plate.

Both of mine were perfectly serviceable and after treatment went back in with the obligatory blakes seacocks grease of which I still have 3/4 tub.
Both turn perfectly now despite being stuck solid.

 

[thesaintlyone]

Sorry just noticed from you pictures that you have the valves out. Guess if you want them off you are gonna need to grind off the nuts etc....

But always worth cleaning with Blakes

 

[burgundyben]

Why replace them?

Now you've disturbed it I would suggest it'll need re-sealing.

You can use fine grinding paste to lap together the cones to great effect. Then reassemble.

As its a Westerley, I suspect its fitted with rally bondite two part sealant, think I can see it in the pic, I'd knock the bolts out one at a time then it should come off easily enough.

You could refit with polyurethane sealant, but i'd consider non setting butyl rubber such as Arbomast BR.

 

[Tranona]

If you do want to replace them with ball valves (of any type) you will have to cover the holes and start again. Waste of time and effort. If you have disturbed the seal then take the bolts out and hammer the bodies out. Clean, lap in the cones and look forward to a lifetime of future service. If you do remove the bodies, reseat with a no setting sealant such as polysulphide and butyl.

 

[macd]

If you hammer the bolts out, pop a nut on them first to protect the thread: someone might thank you for them. In fact someone might be glad of the entire valves if they're not too mangled.

 

[burgundyben]

such as polysulphide and butyl.

Interestingly I found Boatlife Life Caulk to be hopeless. I tried it in several places and it was no good.

If you hammer the bolts out, pop a nut on them first to protect the thread: someone might thank you for them. In fact someone might be glad of the entire valves if they're not too mangled.

Indeed, given that they are bronze and £150 new.

 

[Tranona]

Interestingly I found Boatlife Life Caulk to be hopeless. I tried it in several places and it was no good.

Used it many times with success, including Blakes seacocks. Difficult to find now so use the Arbo equivalent.

 

[JumbleDuck]

Interestingly I found Boatlife Life Caulk to be hopeless. I tried it in several places and it was no good.

I used it all over the place on my last boat and never had problems - apart from the foul smell. What did you find went wrong?

 

[macd]

Indeed, given that they are bronze

That's a moot point. The valves have been DZR brass for decades, but for quite how many seems to be a Blakes secret. Even Sir Vyv (the metallurgist, not the cricketer), isn't sure.

 

[chrishscorp]

Just done the same job on my Westerly 1972, so lasted well. The nuts on the back were lovely and pink the cones were pink, strainer plate fell to bits, and a couple of the bolts sheered whilst trying to undo them pink all the way through, so i changed the lot to be on the safe side.

Nuts back on the bolts a couple of turns and hammer flat with the flange. A 6'' nail with the point cut off makes a good drift, then its a matter of trying to rotate them to loosen them up then drift them out from underneath.
Replaced with bronze skin fittings and DZR valves, skin fittings bedded in on Sikaflex 291. I made 1 new backing pad for the larger fitting as the ply was just starting to go soft.

 

[burgundyben]

That's a moot point. The valves have been DZR brass for decades, but for quite how many seems to be a Blakes secret. Even Sir Vyv (the metallurgist, not the cricketer), isn't sure.

I didn't know that! In my book, DZR is as good as bronze.

 

[macd]

In my book, DZR is as good as bronze.

I suggest you do a book exchange

 

[Jokani]

Why do I want to replace - I re-lapped the valves last year but there is some really heavy pitting, they are also very worn, I'm just happy to replace with something more modern.

Thanks for all the tips on removal, will let you know how I get on.

But also check out Tru Design valves and fittings. They might just be more convenient than Marelon as replacements for Blakes seacocks

.

Thanks for the tip Vic, the Tru Designs do look easier to fit, I have ordered them from Leesan

 

[macd]

Thanks for the tip Vic, the Tru Designs do look easier to fit, I have ordered them from Leesan

Perhaps too late, but you might find them cheaper here: https://www.svb24.com/en/trudesign-ball-valve.html

 

[burgundyben]

I suggest you do a book exchange

Why?

(Not being deliberately obtuse, just would like to understand the specifics of why you think DZR is less suitable than bronze)

In 'my book', bronze is a term applied to many materials, some of which are in fact brass.

In application, I have seen nothing to suggest that the lifetime of a DZR part is limited?

 

[macd]

Why?

(Not being deliberately obtuse, just would like to understand the specifics of why you think DZR is less suitable than bronze)

In 'my book', bronze is a term applied to many materials, some of which are in fact brass. DZR is a type of brass.

But, in application, I have seen nothing to suggest that the lifetime of a DZR part is limited?

Obviously neither of us was specific, but I was referring to a 'true' bronze: i.e. a copper/tin alloy. You're certainly right that many so-called bronzes are nothing of the sort: many of our props, for instance, although their alloy has other desirable properties. Equally some pseudo-bronzes, such as silicon-bronze, are ideal for fasteners because of their high mechanical strength.

Of course DZR brass is a type of brass. That's why it's called 'DZR brass', the 'DZR' merely being a property, albeit once commonly used as shorthand. I wasn't trying to suggest that it isn't fit for purpose on underwater fittings, just that I think an appropriate true bronze is better. I think the clue is in the 'R': an 'I' (for 'immune' or something like it) would be more reassuring.

Would I fit DZR brass skin fittings? Yes, I would, although the next round of changes will be to composites.

Of course if Vyv differs, I'm all ears.