Yamaha F200 Skeg Corrosion

[tjiann]

We took possession of our R23 last year here in MD. We keep it on a lift. To my surprise and dismay, the skeg on the Yamaha F200 outboard is corroding away. It is only in the water when on our lift for brief periods when the tide is very high and the water is brackish in our creek. Why is this happening?

 

[NorthernFocus]

Do you have any photos? If the skeg is routinely submerged but not deep enough to wet the zinc anode then it is not being protected by the zinc. Still if the boat is only a year old it is surprising if the coating on the skeg has already broken down. Photos would be helpful.

 

[gsc3]

If your boat is plugged in to shore power, without having a galvanic isolator, galvanic corrosion is a possible culprit. Nearby submerged iron or steel that is grounded can cause galvanic corrosion of submerged aluminum in salt or brackish water. The Yamaha lower unit on our Cutwater 24 was badly damaged by this process.

Slade Cargill

 

[tjiann]

Thanks for the replies on this folks. I've learned a lot about this the last few days. First time owning a boat where I plug into shore power at home. I'm having our lift guys come out to see if they can get the boat up a bit higher so the skeg will never be in the water. For now, I'm keeping the engine up.

Anyone have opinions on skeg guards? I may install one just to protect/stabilize the skeg where the corrosion occurred. Any particular brands better than others?

Also, I know there was a request for photos, but I have not been able to figure out how to post those in this forum yet.

Thanks,

Tim