Anodes and when necessary?

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mm5aho
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Anodes and when necessary?

Post by mm5aho »

Contender has lasted 41 years without anodes.
She has a fibreglass hull, and metal contacting seawater includes the following...

Seacocks fed by plastic hoses (electrically isolated from other things, except the conductivity of the sea). These are bronze where in connection with sea.

Prop and propshaft with partially exposed bearing. This connected to the gearbox mechanically, but isolated electrically through a flexible propshaft joint. Prop bronze, shaft stainless.

Should I have an anode? What is likely to be forming a corroding circuit with what? If requiring an anode what should it be connected to?
The prop shows a very small amount of corrosive wear, but for its age pretty insignificant. The prop is >20 years old.
Geoff.
"Contender" Rival 32: Roseneath in winter, Mooring off Gourock in summer.
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Rowana
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Re: Anodes and when necessary?

Post by Rowana »

I would say; If it ain't broke, don't fix it.

But that's just my opinion.
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sahona
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Re: Anodes and when necessary?

Post by sahona »

I have to agree with Rowana - unless you've changed something recently, like moving to a marina full of faulty boats. None of the boats I've had since the mid sixties have had internal ground wires to the skin fittings, and I didn't suffer anything nasty. Sahona has a connection from a pear anode to the stuffingbox as there isn't enough shaft showing outside to fit an anode. Other boats only had shaft anodes.
I bet you've got the wherewithall to make a special anode that attaches to the prop if required.
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mm5aho
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Re: Anodes and when necessary?

Post by mm5aho »

Thanks, as I thought too. If it hasn't corroded by now, and no major changes, then probably not required.
I do have access to plenty of zinc though....
Geoff.
"Contender" Rival 32: Roseneath in winter, Mooring off Gourock in summer.
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