Anodes on bow and stern thrusters Beneteau Antares 30

Nigel52

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I’m used to annually changing the anode on my bow thruster on my QS 905WE at the same time I change my outdrive anodes. Does anyone that owns or has owned a Beneteau Antares 30 with bow & stern thrusters know if this is a requirement?
 

Tranona

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The requirement is independent of the boat/thruster type. Anodes need to be changed when they are roughly 50% down by weight. Rate of wear varies dependent on many factors related to the individual bit of kit and boat. Thruster anodes are small and do tend to last for a relatively short time. My Sidepower lasted typically 3 years in the last boat, but similar in current boat changed after 18 months. They are low(ish) cost so many change them every year.
 

Nigel52

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The requirement is independent of the boat/thruster type. Anodes need to be changed when they are roughly 50% down by weight. Rate of wear varies dependent on many factors related to the individual bit of kit and boat. Thruster anodes are small and do tend to last for a relatively short time. My Sidepower lasted typically 3 years in the last boat, but similar in current boat changed after 18 months. They are low(ish) cost so many change them every year.
It has certainly been my view to change them annually. What is interesting is how few people ensure these are changed. I was particularly interested in Antares owners to see. If they ensure it is done and if they do it themselves how easy are they to replace?
 

jfm

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100% agree with Tranona - this has little to do with fixed time intervals whether a year or any other time period. Just change them when worn to about 50%. Annual is typical enough, but it depends on your boat's circumstances and your marina environment.

I'm perplexed by your statement "what is interesting is how few people ensure these are changed." What's your data or source of info for that premise? Sure there will be some neglectful boat owners but generally I see these being changed by most people and most boatyards, when required.

It's a 10 minute job and usually an allen key is all you need - one socket head cap screw of about M6 size holds each anode on.
 

Seastoke

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Peeps change them yearly as it’s when boat is out for AF so makes sense . They are not expensive and you would not what a lift out just to change an anode.
 

Bouba

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There’s also the problem of mixing anode material......for example it’s difficult to find QuickSilver thruster (found on some Beneteaus) anodes that aren’t made from aluminum....and the rest of your boat might have zincs
 

Nigel52

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There’s also the problem of mixing anode material......for example it’s difficult to find QuickSilver thruster (found on some Beneteaus) anodes that aren’t made from aluminum....and the rest of your boat might have zincs
You raise a completely different issue here and that is the Mercruiser school of thought that says aluminium anodes are better than zinc and other manufacturers say go zinc. But good point not to mix.
 

Tranona

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The "not to mix" is not proven. There is some evidence that anodes in close proximity although not connected - for example on saildrive housings and isolated props should not be mixed, but little evidence that anodes at opposite ends of the boat that can't "see" each other have to be the same material. The potential of zinc and the aluminium based alloy used for anodes are virtually identical. Aluminium is rapidly taking over from zinc, particularly on things like saildrives, outdrives and bow thrusters where the manufacturer specifies the material used. General purpose hull mounted anodes and shaft anodes still tend to be zinc.
 

baldyash

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I’m used to annually changing the anode on my bow thruster on my QS 905WE at the same time I change my outdrive anodes. Does anyone that owns or has owned a Beneteau Antares 30 with bow & stern thrusters know if this is a requirement?
My A30 has no bow thruster anode but stern is a small conical item with a Allen key bolt through the centre
 

PeterBoater

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The requirement is independent of the boat/thruster type. Anodes need to be changed when they are roughly 50% down by weight. Rate of wear varies dependent on many factors related to the individual bit of kit and boat. Thruster anodes are small and do tend to last for a relatively short time. My Sidepower lasted typically 3 years in the last boat, but similar in current boat changed after 18 months. They are low(ish) cost so many change them every year.
I think the 50% figure that is often quoted might well have come from anode makers and marine engineers (as the lady said, they would say that, wouldn't they?), and is too broad brush, even as a rule of thumb. If an anode has a historical wear rate of 50% a year and the boat is lifted out once a year, then, yes, replace at 50% is a good figure. However, if the observed historical wear rate is 20% a year and the boat is lifted out twice a year, then quite possibly the anode could last at least four years, ie replace when 80% of original mass (weight) worn. As written above, it depends on many factors.
 

Tranona

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I think the 50% figure that is often quoted might well have come from anode makers and marine engineers (as the lady said, they would say that, wouldn't they?), and is too broad brush, even as a rule of thumb. If an anode has a historical wear rate of 50% a year and the boat is lifted out once a year, then, yes, replace at 50% is a good figure. However, if the observed historical wear rate is 20% a year and the boat is lifted out twice a year, then quite possibly the anode could last at least four years, ie replace when 80% of original mass (weight) worn. As written above, it depends on many factors.
You are right of course. but many boats do get through more than half an anode a year, particularly if the boat is in the water all year round. It is therefore a useful reminder to ensure that your anode ha enough meat in it to last until the next planned haulout.
 

Bouba

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I have often suspected that when an anode gets covered in scum and slime, that they aren’t as effective....I always try to scrub them if I’m swimming. I don’t know if this is true or not
 

Seastoke

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I have often suspected that when an anode gets covered in scum and slime, that they aren’t as effective....I always try to scrub them if I’m swimming. I don’t know if this is true or not
With you pumping that stuff out of those pipes nothing will come close to your boat .
 
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