Bummer!

[sahona]

Been working on all the usual stuff, Milton in the freshwater system, Engine filters, inhibitor, stern and rudder glands, as you do at this time of year (boat is afloat).
Having greased and tightened the rudder gland to stop the minute trickle that had developed, I was curious about the water still accumulating under the aft cabin floor. It was coming down from the side though, so I felt under a locker and was surprised - nae gobsmacked, to discover a stub of screwed stock with two nuts and cables on, which used to be attached to the anode outside...
As I touched the area where the screw used to live, I sensed the incoming trickle of water increasing so I hastily withdrew and started planning. There's a queue for the scrubbing grid and a boat on there at the moment. I'll just have to hope that the automatic bilge pump is actually functional - the sensor was last checked about a year ago although the pump works manually.
Back in the shed I've identified the bits I need and will make up a replacement stud tomorrow and fit it whenever I can get dried out.
So I guess it's just another thing we should be checking when we change anodes - but who bothers to look at the inside?

[claymore]

I keep a packet of underwater epoxy putty for just such a dreadful event.
Hope you get it fixed quickly - can you pull rank and jump the scrubbing grid queue?

[Gardenshed]

sweet talk Duke for a wee shot of his new remote controlled hoist. tell him he needs some practice


(then retire to a safe distance)

[wully]

I keep a role of Denso tape in a bag along with disposable gloves in case of nasty leaks..

[sahona]

It's worse than that Jim...
This was what I saw from the inside


and this was my first view of the outside, Notice the lack of stud and nut on the aft end of the anode. Just a serrated washer.


I loosened the remaining nut and swung the anode to reveal this


I had to make one of these in the shed

As this is all that was left of the original, apart from the nuts and stuff I found detached inside.

Yes that's the square plate that was welded to the stud which had turned into black sludge.
It was all healthy this time last year when I changed the anode, so I can only guess that there was a poor connection between the anode and the stud which then became sacrificial.
I'm lucky I caught it when I did, as the water pressure would eventually have pushed the sludge out of the hole, which at 12mm would have given the bilge pump and batteries plenty to think about.
Pity the high tide was midnight, it made for a long day, but worth it.

Notice how low the tide went! We don't usually have so many drunken boats in the club. Wonder what Dunstaffnage was like ?

[cpedw]

It was all healthy this time last year when I changed the anode, so I can only guess that there was a poor connection between the anode and the stud which then became sacrificial.

Do you have any thoughts on how to prevent a recurrence? I remember the first time I asked about this plain steel holding the anode in place, I was assured that being so close to the anode, it was just fine. Now we know different. I'm worried!
Derek

[cpedw]

Coincidentally, there's a thread in TOP on another anode problem http://www.ybw.com/forums/showthread.ph ... node-studs
VicS has the authoritative solution to hand.
Derek

[sahona]

Oddly enough, I'd read Vic's thread and was aware of the different materials conundrum just before my incident. I also firkled about on the net before deciding to make my own stud. They are having a larf aren't they.
As to the cause of the problem, I can only surmise. The original stud was probably installed in 1978 and was OK until this year, so it wasn't the wrong material and there have not been any recent changes to the boats galvanic circuit or environment, so I assume I failed to make a good electrical connection to the zinc. This time there are two serrated washers installed between cleaned faces.
Theoretically I could glass a thin membrane over the inside connection which would keep the water out but be easily ground off if needed - no I'll stop thinking like that or they'll come and take me away again.

[Booby Trapper]

Will this be your last attemt at sinking the old girl? You've tried twice (that I know of) and failed.....

Very low tide!! could get nasty if two of them next to each other decided to go opposite ways.

[Booby Trapper]

Oops sorry Bill I must think before I type I'm sure you know it was just a joke. After my last misunderstood post on TOP I must stop upsetting people. Have some smilies :

[sahona]

No probs Ian. As you say it's a bit deja vu, however experience is always good - I was quite confident that this time I wouldn't go through the phase when I realised the water was going to win! Calm and philosophical - home, sleep (soundly), visit shed, visit grid, home in the dark, job done.
Still a bit worrying that it can happen though, I guess checking the ohms should become part of the anode renewal process - easily done from the inside (periodically?) across both the studs.