What is this piece and how can i clean it?

[AleCiotti]

Hi guys, i'm a bit of an ignorant here, what is the plastic/rubber thing on the photo below? what is it's function?
Also what is that small hole, is it for a pencil anode?

It is very corroded so I assume there is an anode missing somewhere..
How can I clean that rust? is a rust converter enough or do I need to use something else?

Thanks!

[Orion Jim]

It appears to be a flexible drive shaft coupling.

[boatpoker]

Looks to be a Vetus flexible shaft coupling. Anodes are not fitted to anything that is not immersed in water.
https://www.vetus-shop.com/vetus-bul...5mm-p-974.html

[Tortuga's Lie]

Flexible coupling. The hole is for a set screw, probably stacked. A stacked set screw means that one screw is inserted and screwed tight, a second one is added so the first one doesn't back out, kind of a locking mechanism. This is done in critical locations, such as a shaft coupling.

[boatpoker]

https://vetus.com/wp-content/uploads...g-BULLFLEX.pdf

[AleCiotti]

thanks for the links! it looks to be it.
And how do I go about cleaning the rust? and why could it be there in the first place?
Thanks

[Kd9truck]

I would use CRC electrical cleaner, spray everything, paper towel wipe clean and wire brush the rust off a wire wheel in a screw gun works great. Then use an oil base motor paint. The motor mounts look like they need to be replaced as well but I’m just looking at a picture.