Replacing seacocks is a straightforward job, and on Maximus it's not worth trying to salvage them, advises marine surveyor

The worn seacocks on PBO Project Boat Maximus are going to have to go. During the survey of the 28ft Maxi 84, marine surveyor Ben Sutcliffe-Davies points out that they’re clearly over 5 years old and corroded.

He also notes that the hose tails are incorrectly clamped.

“This one makes me laugh because we talk about double clamping but the clamps aren’t actually on the end of the hose tail,” he said. “They’ve double-clamped but it’s completely pointless.”

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The fittings look to be DZR (dezincification-resistant) brass, though on later inspection, they’re reported to be zinc-plated brass, which is totally unsuitable for use under the waterline. They will all need replacing.

“If they were bronze, you’d probably get more life out of them,” says Ben. “Bronze lasts a lot longer, and certainly with Blakes valves in particular, normally they just need a good service. Just watch the fastenings going through the hull.”

Ben tries the handles. One of them is seized, there’s a bit of movement in another and the third works ok, but he says, “Frankly, over five years old, chuck them out and start again”.

He advises that a lot of people are going for the TruDesign or Forespar Marelon. The Alex valve is another good one. 

Ben also takes a look at the sink unit, but it takes him a while to find the seacock as the discharge hose runs across the galley. After removing the saucepans from one cupboard, he finally finds it in the bottom drawer. It’s an old-fashioned sluice valve and is completely seized.

“That’s something else that will have to be changed or freed off,” he says. “It’s more likely to be bronze. Bronze is better than DZR but frankly for the sake of a few of quid I’d start with a new valve in there completely. It’s very awkward where it is, so that’s going to be fun for someone!”

We’ll be replacing the seacocks on Maximus before we launch, and have decided to go with TruDesign. You can follow our progress on YouTube and here at PBO.

Here is the article about how we replaced the seacocks and skin fittings on Maximus.


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