What are these???

[rgardner928]

So I own a 97 Seadoo Speedster. I have stripped most of it and replace what I could. But I noticed these are mounted in about the same spot under both pump housings.

Can anyone tell me definitively what they are, and what they do? They are bolted on with a hex bolt and appear to be white and feel like ceramic when touched.

I have 2 friends that have the exact same boat, year and all. Both of theirs do NOT have it. But my plastic pump mounting area appears to be different on mine where theirs is identical to each other.

Any ideas?

 

[rgardner928]

Friend one's boat...notice he has a divider on his and they are not on his. Nor is there mounting holes for them.

 

[rgardner928]

Friend two's boat...notice his is identical to friend ones boat.

 

[mikidymac]

They are Zinc anodes to prevent corrosion on metal parts.

 

[rgardner928]

But its not wired to anything.

 

[mikidymac]

Doesn’t have to be. That’s what it is.
Someone probably added them since they aren’t on the diagram for your boat.

 

[rgardner928]

Ok..understandable..but how does the Zinc Anodes work in theory.

 

[ronmold]

If they're not electrically connected to anything then all they will protect from corrosion is the bolt that holds them on. They must be bonded to the metal you want protected that contacts the water like the engine block which in turn would protect the prop shaft and impeller. Zinc is better for salt water than freshwater and the need in freshwater would depend on how acidic (or alkaline) the water may be. It looks like yours have been doing nothing as when they are installed correctly and working they will corrode away and yours still has the raised writing untouched. The theory is that water (unless 100% pure distilled) will corrode metal so we give it a more reactive metal that we can easily replace than our props and shafts are made of which would be zinc or better yet magnesium,

 

[rgardner928]

If they're not electrically connected to anything then all they will protect from corrosion is the bolt that holds them on. They must be bonded to the metal you want protected that contacts the water like the engine block which in turn would protect the prop shaft and impeller. Zinc is better for salt water than freshwater and the need in freshwater would depend on how acidic (or alkaline) the water may be. It looks like yours have been doing nothing as when they are installed correctly and working they will corrode away and yours still has the raised writing untouched. The theory is that water (unless 100% pure distilled) will corrode metal so we give it a more reactive metal that we can easily replace than our props and shafts are made of which would be zinc or better yet magnesium,

Thanks for explaining...this was extremely helpful. I wasnt the one that installed it. Not sure how to get it wired into the boat from those points. But I will never be in salt water. This is a now a freah water boat. The water it sees will all be water from the Colorado river and Lake Havasu. They dont feel like metal, but more of a ceramic or stone feel. But what do I know. Would you suggest I somehow figure a way to wire it to the engines? (Not sure how) Or just leave them for show, sincd its in fresh water from Lake Mead...lol

 

[ronmold]

Lake Mead is a bit alkaline, wouldn't be a bad idea to ground one of those if you could figure out how to do it, especially if it lives in the water and not on a trailer. Galvanic activity may be one of the reasons the welded in water jacket plugs on our tuned exhaust pipes tend to corrode through. I'm sure they're at least 1/8 inch thick when welded in but one of mine was paper thin and starting to leak. It may be a more reactive aluminum alloy than the rest of the casting, possibly on purpose.

 

[rgardner928]

No...this boat is trailer stored. It sees all of about 20hrs of water time on average a month, none of which is ever stored in water.

To ground basically run a wire from the mounting screw to my engine block?

 

[mikidymac]

Honestly in fresh water there is no reason to have it at all.

If you want to go crazy connect a stainless wire from it to the stud that holds the pump on that goes through the hull. Then on the inside connect a wire from that stud to the engine. It is a waste of time and not necessary though.

There is no metallic connection from the rideplate to the engine.

 

[rgardner928]

Thanks for everyone's input.

 

[ronmold]

Yes I'll agree with mik, in your case not worth the effort.