What Is this on the Bottom of My Boat ?

[flatlander]

I pulled the boat for the winter (this is the first haul out since I've owned the boat), and I found this under the waterline (my hand is for scale). What is this, and what is it for?

[Vasco]

Looks like an old sacrificial zinc. Maybe this is why your prop fell off.

[boatman61]

Anode...

[David_Old_Jersey]

Not 100% sure, but looks like your Zinc

And that someone has really gone to town bodging the fixings. PO's

[Celestialsailor]

What is it connected to on the inside of the boat? When I bought my boat, I had the same affair. The through-hull next to it snapped off in my hand and when trying to remove the prop, it's blades crumbled. Luckily the rudder Gudgeon s were unaffected.

[nigel1]

Originally Posted by David_Old_Jersey

Not 100% sure, but looks like your Zinc

And that someone has really gone to town bodging the fixings. PO's

+1

Those fixings look like stainless. I recall reading somewhere that SS fixings should be avoided on anodes, as SS in contact with the zinc leads to a build up of something or other which creates a large electrical reistance, rendering the anode useless

[flatlander]

I was concerned about the zincs being gone, I just didn't know since I hadn't yet seen the underside of the boat. Over the course of the past year, the boat seemed to have less and less power. I just figured there were barnacles or something on the prop, but I guess it could have also been the blades disintegrating.

[David_Old_Jersey]

Originally Posted by flatlander

I was concerned about the zincs being gone, I just didn't know since I hadn't yet seen the underside of the boat. Over the course of the past year, the boat seemed to have less and less power. I just figured there were barnacles or something on the prop, but I guess it could have also been the blades disintegrating.

Not to cheer you up , but a close look at the shaft would be no bad idea. and your through hulls.

[Blue Stocking]

The boat needs a serious examination, by a professional, as to the condition of all underwater metal.
If you replace zincs in that location, use bronze threaded rod, full nut inside, jam nut outside, with large bronze washers in and out. make rod long enough to accept zinc over rod, and bronze nut outside to hold zinc in place.

[senormechanico]

Originally Posted by Vasco

Looks like an old sacrificial zinc. Maybe this is why your prop fell off.

+1 !!

[Noname]

I hope it ain't screwed into the hull!!!!!!!!!!!

[Philsboat]

I zinc you might have an electrolysis problem

[Target9000]

Hey bubba, I need to change the zinc. Hand me a phillips AND a flat.

[Celestialsailor]

Originally Posted by nigel1

+1

Those fixings look like stainless. I recall reading somewhere that SS fixings should be avoided on anodes, as SS in contact with the zinc leads to a build up of something or other which creates a large electrical reistance, rendering the anode useless

I think Bronze will do the same. Here was my scary project when I bought my boat.

[delmarrey]

A Hawaiian symbol for Shaka