Sterndrive Anodes

JawsOrca · August 4, 2015

Hey all,

We are worried a little, we noticed that our sterndrive anodes are wearing down a bit quick (and there's a bit of surface rust on the stainless hose clips). We are moored close to St olaves the yard advised the water is fresh water (and they confidently said this and they have been for many many years so certainly know their yard) so therefore our surveyor told us to fit Magnesium anodes (and two of them). (They are probably about 1/3 to 1/2 worn (in 4 months). The leg looks perfect condition still thankfully. We do not have 240v connection and there are no loose cables earting anything incorrectly. The anode was provided by sillette and we doubled it on recommendation of the surveyor (so we have technically doubled up anyway). Basically, We are a bit worried that the water here is brackish and not fresh therefore the magnesium anodes aren't correct and we should be using Alloy ones (But I'd rather use the more reactive ones).

I'm thinking just replace the ones we have in a couple of months which should make it through the season but then it's used 4 anodes in 12 months.

Any thoughts?

cheers

diesel falcon · August 4, 2015

:norty: :norty: you need ally anodes, the water is brakish where you are(weak yess but brakish) mag anodes will just fizz away at a pace, i reckon to get about 2.5 years from ally one,s, as for the clips you need the full salt water one,s, i forget the stainless number but someone will know, we moore at st olaves :wave

Baitrunner · August 5, 2015

Alan, Just to add my comment ally are what you need.

I have them and know people at Reedham who use the same.

JawsOrca · August 5, 2015

Ok Thanks to you both ..

I do more reading late last night and I'm tending to agree..

I've found Navalloy?! (http://www.performancemetals.com/anodes/navalloy.shtml) which on paper look bloody good.. I've emailed Bryan wards and hopefully they can source for me and we can fit this weekend.. From what I've read these mag ones are working although are overprotecting so very short term the legs ok but I do want them changed asap.. Can't believe it's been so confusing!!

cheers

Baitrunner · August 5, 2015

Alan,

When I got my current boat a very large boat sales organisation (not on the Broads), tried to convince me I needed Mag anodes, despite my engineer telling me I needed Ally.

The said company refused to buy the Ally ones as they were not Volvo parts (apparently Volvo don't make Ally anodes for my legs). In the end we bought the Ally ones and they fitted them as part of the sale so even the best can give duff advise or be just plain annoying.

From what I have been told most boats down South are on Ally.

JawsOrca · August 5, 2015

It does seem even our surveyor is confused though as technically the broads are fresh water but considering the tidal range down south I suspect a lot of it brackish. Although even sillette the makers of the leg refused to provide Alloy anodes and provided Mag ones so yup I'm not happy.. Thankfully we have spotted it before any damage has been down.

Hopefully I can find a suitable replacement though.. We fitted Mcduff "MJE1" which is a "Universal stern drive anode" so hopefully they can.. Do you think any alloy anode will do or should I push to get this Navalloy one?

Baitrunner · August 5, 2015

Alan, I am not an expert on the different types, but I would think any would do - Just keep an eye on them if you can to make sure they are working.

With stern drives at least you can lift them to have a look without a haul out.

JawsOrca · August 5, 2015

Yeah luckily we can see them when the waters clear.. Sadly it's not in the marina but down towards beccles etc it's ok.. We should be able to lift it enough to change them or jumpt in the dinghy and do at least. It's coming out for a service in the winter anyway.. although it will be a lift, service and back in.

cheers

Baitrunner · August 5, 2015

Come on Alan put some effort in.

On my recent Caribbean adventure the guys in the marina had to replace a prop before we could take the boat out. Swim shorts, spanner, pliers and a dive mask was all he had!!!

ps. Up at Whitlingham the water can be really clear as well if you need a peek down below.

JawsOrca · August 5, 2015

Yeah.. I bet the water was also lovely and warm and crystal clear and they was taking a dip anyway... The brown coloured freezing cold waverney is something else lol

Thanks for the Whitlingham tip..

cheers