Trim tab anodes

Cathy*

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Merry Fisher 895 finally arrived yesterday :) We're having her out of the water for 2 weeks to do the stuff you have to do. We're surprised to see anodes on the top and bottom of the trim tabs. Other 895 owners have said that's how they come but a trawl of t' interweb, including anode suppliers and Bennett say top only. What say you?
 

Plum

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Merry Fisher 895 finally arrived yesterday :) We're having her out of the water for 2 weeks to do the stuff you have to do. We're surprised to see anodes on the top and bottom of the trim tabs. Other 895 owners have said that's how they come but a trawl of t' interweb, including anode suppliers and Bennett say top only. What say you?
I've never seen them on the underside. Suggest you look here. Trim tabs and anodes
 

jon and michie

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As @Plum says Ive only seen them on the top are they bennett Trim tabs ? maybe have a look if they have included the instructions in your docs.
My bennett Trim Tabs where made from stainless steel, had plastics rams and had just the one anode on the top
 
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Cathy*

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As @Plum says Ive only seen them on the top are they bennett Trim tabs ? maybe have a look if they have included the instructions in your docs.
My bennett Trim Tabs where made from stainless steel, had plastics rams and had just the one anode on the top
We've only ever seen them on top too which is why I'm questioning this. It seems other MF 895's have the same. I will try to find paperwork today but we're going to put just one on the top and see how we go.
 

colhel

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Mine are only on the top too and I haven't changed them in the five years we've owned the boat. The tabs are hydraulic and I can't think of any dissimilar metals being used, which I assume slows down the anode depletion?
 

oldgit

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Always on top ?
My tab anodes are supposed to be some custom items designed especially for the trim tabs fitted to my boat.
They are of course eyewateringly expensive items, not normally kept in stock at your average chandlery and hard to find even on the interweb.
They were replaced with a bog standard ring anode of a slightly heaver weight. and at considerably lower cost.
Cannot recall ever seeing a trim tab anode fitted underneath,this would surely cause drag and prevent the laminar flow of the water.
 

Cathy*

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Always on top ?
My anodes are supposed to be some custom items designed especially for the trim tabs fitted to my boat.
They are of course eyewateringly expensive items, not normally kept in stock at your average chandlery and hard to find even on the interweb.
They were replaced with a bog standard ring anode of a slightly heaver weight. and at considerably lower cost.
Cannot recall ever seeing a trim tab anode fitted underneath. This would surely cause drag and prevent the laminar flow of the water.
Laminar flow 😀 I had to Google that and I agree. When we had Beneteau boats there was no option but to buy their prop anodes but with the last one we bought the biggest possible from UK Anodes, now anode outlet. Their prices are good but as we only need 2 we're going to pick them up at Marine Super Store in Port Solent.
 

oldgit

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Always a good idea to get your anodes long before you need them, especially prop and shaft anodes. the prices can vary dramatically.
We are lucky enough up here in North Kent to have several companies who smelt anodes, can collect from the factory, prices reflect this.
Anode Outlet do appear to be offering some very good value and we can collect from Pirates Cave our local chandler.
Sometimes from off the shelf.
No need to spend a fortune buying those pencil anodes complete with new brass cap either , just buy replacement zincs and screw into your existing old brass cap.
Usually a pair of pliers will remove old zinc but you might have to clean out threads in cap a bit. You can be quite rough and have used a drill to clean out cap.
If you have 4 or 5 anodes per engine and two engines a considerable saving,
Sorry but no fancy packaging with any of this stuff ,suggest you bring your own plastic bag. !
 
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Plum

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Mine are only on the top too and I haven't changed them in the five years we've owned the boat. The tabs are hydraulic and I can't think of any dissimilar metals being used, which I assume slows down the anode depletion?
Agree. As i posted in another thread in June 2023: "I have been unable to find any reliable data on this and agree that Stainless Steel, not in contact with any other metal, is unlikely to need an anode. I dispensed with the anodes on my Bennet trimtabs 5 years ago (it was worth the risk as I have found they provide no real benefit on my boat and if they fail would not replace them). Checked them this week while out of the water. No sign of any deterioration."
 

PaulRainbow

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Fitting an anode underneath a trip tab makes no sense at all, one on the top provides all the protection you need (as per post #10, debatable if they are needed at all).

Oldgit is correct about drag too.
 

ss2016

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My Sargo came from the factory with anodes fitted top and bottom. They get noticeably 'eaten' in a season. I guess it makes for easy attachment.
The anode which is as good as new after 3 seasons is the transom shield anode.
I can believe the tab anodes might reduce the speed by 0.00...1Kts!




IMG_20220106_092946988.jpg
 

wonkywinch

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from UK Anodes, now anode outlet. Their prices are good but as we only need 2 we're going to pick them up at Marine Super Store in Port Solent.
I'd give Anode Outlet a miss. Boat out of the water with a week to go to launch, ordered a couple of bow thruster anodes. "In stock, ordered by 1pm for next day delivery". I didn't order til 3pm Mon so expected a Tues shipment, delivery Wed. By Thurs, nothing heard so I emailed them first thing. No response by 3pm so called them. "Just picking your order now, will be shipped today". A courier notification later received saying "order raised, awaiting package from retailer". Now Sat nothing seen or heard so emailed this morning for a refund and popped into the chandler. Still no response to my email.

Great prices but false "next day" promise and emails go into a black hole.
 
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