Sea cocks

[ianc1200]

Following a purchase survey, I need to replace four sea cocks, these are the inlet & outlet one's for two toilets. It's been mentioned to me plastic sea cocks are available, which I've never heard of before. My inclination is to get the best bronze (Blakes?) available, but are these plastic one's any good?

 

[bendyone]

Tru Design work well for me Tru Design

 

[doug748]

This is worth a read:

Marelon Seacocks Failure!!!!

The blog referenced is no longer up but I recall a forum member having a failure - which is probably the one referred to in that blog.

.

 

[Tranona]

Following a purchase survey, I need to replace four sea cocks, these are the inlet & outlet one's for two toilets. It's been mentioned to me plastic sea cocks are available, which I've never heard of before. My inclination is to get the best bronze (Blakes?) available, but are these plastic one's any good?

Depends on what type they are. If they are Blakes, highly unlikely they need replacing. If they are ball valves then you essentially have a choice of metal (DZR) or composite (Tru Design). Either will suit but you need to replace all the fittings, not just the valves.

 

[ianc1200]

Thanks for the replies.

 

[Plum]

Depends on what type they are. If they are Blakes, highly unlikely they need replacing. If they are ball valves then you essentially have a choice of metal (DZR) or composite (Tru Design). Either will suit but you need to replace all the fittings, not just the valves.

Totally agree re DZR but just to add that DZR fittings and ball valves from ASAP Supplies are very good. I replaced one of mine from them after 15 years just because I wanted to investigate it's condition even though it was still working perfectly. On investigation looked good. Hacksawed it in half and there was no dezinking at all. Gave me confidence in the others.

By the way Blakes quote their seacocks are of "Cast DZR Brass/Bronze components:

 

[Tranona]

By the way Blakes quote their seacocks are of "Cast DZR Brass/Bronze components:

They have been for over 40 years, long before the material became common in ball valves.

 

[Bouba]

I like Tru Design......but it can be difficult to source the parts (at least here) and you need room inside the boat hull as these fittings sit high. Have a look inside the boat, access to seacocks isn’t as good as it should be....start with the question, what will fit

 

[Boathook]

In the UK https://www.tek-tanks.com/product-category/plumbing-equipment/trudesign/ and Tru Design Products - Seacocks - Hose Tails

Maybe other places as well.

 

[Bouba]

With Tru Design it’s good to use the collars ....especially if the fitting is somewhere that can be subjected to lateral forces (ie...if you trip over it...or your tool box slides into it)
Tru design Load Bearing Collars

 

[trialframe]

On my Nordhavn which is fitted as standard with quality bronze seacocks - I needed to renew a retro fitted inferior quality one.
I used a Groco bronze one - available in the UK at reasonable prices and nice quality.

 

[LiftyK]

I was about to remove and service my Blakes seacocks when I realised that they are still silky smooth. That's another year with no maintenance needed. They're great.

 

[Boathook]

I was about to remove and service my Blakes seacocks when I realised that they are still silky smooth. That's another year with no maintenance needed. They're great.

Tru design don't mention servicing. The other dzr seacock is regularly operated and also works well.

 

[Richborough]

I was asked to help strip out a huge barge . When I went below 5 flex hoses laying acccross the decks . Sea cocks fully open. I pointed kout to the new owner that his barge could possibly sink if your don't shut those off.

 

[Tranona]

I was asked to help strip out a huge barge . When I went below 5 flex hoses laying acccross the decks . Sea cocks fully open. I pointed kout to the new owner that his barge could possibly sink if your don't shut those off.

Why would that happen if the decks the hoses were running across were above the waterline?

 

[Richborough]

why because all the crap in the barge was stacked to the port side making the barge list

 

[Tranona]

why because all the crap in the barge was stacked to the port side making the barge list

So the outlets of the hoses were under water? The cockpit drains on my boat are open at the top and I leave the seacocks open. It has not sunk yet.

 

[Fire99]

Last year I replaced one of my heads seacocks for a Tru-Design. They are chunky beasts so you do need reasonable access but reviews are very good and it's another fitting that no longer needs bonding against corrosion. My intention is to stick with the hefty bronze seacocks for engine inlets but as I replace others, I'm inclined to shift towards Tru-Design wherever access is possible..

 

[Tranona]

Last year I replaced one of my heads seacocks for a Tru-Design. They are chunky beasts so you do need reasonable access but reviews are very good and it's another fitting that no longer needs bonding against corrosion. My intention is to stick with the hefty bronze seacocks for engine inlets but as I replace others, I'm inclined to shift towards Tru-Design wherever access is possible..

Bonding does nothing to reduce corrosion of seacocks. They are either corrosion resistant (DZR), bronze, or composite like Tru Design which do not corrode. If however they are plain brass which is often an alloy of 60% copper and 40% zinc then may well dezincify over time - but bonding to an anode will not prevent it happening.

 

[Fire99]

Bonding does nothing to reduce corrosion of seacocks. They are either corrosion resistant (DZR), bronze, or composite like Tru Design which do not corrode. If however they are plain brass which is often an alloy of 60% copper and 40% zinc then may well dezincify over time - but bonding to an anode will not prevent it happening.

Interesting as my Boat has from factory all of the seacocks bonded.. I shall consult with Nigel Calder again and see his take on seacock bonding..