Prop shaft coupling

[gonesail]

My coupling is not rusted after many years but I found one of the set screws to be a little lose. I plan on buying 2 more and redoing the lock wires as well. You might check yours to see how they are holding. Also you might consider installing a shaft retention collar.

[wingless]

Originally Posted by Reefmagnet

I wouldn't be inclined to paint because paint won't adhere to rust scale all that great. If you coat it with something like Tectyl, it can be easily recoated as needed.


https://tectylproducts.com/

Originally Posted by wingless

They have lots of products.

This one says clean and rust free first.

Which product protects a rusty part?

Originally Posted by Reefmagnet

506, I think

This is from the manufacturer's data sheet.

The maximum performance of TECTYL 506 can be achieved only when the metal surfaces to be protected are clean, dry and free of rust, oil and mill scale.

[wingless]

Originally Posted by wingless

That steel coupling may be polished up to look like chrome.

That part is fine, just surface rust.

When I do those parts I first polish to a chrome finish, then apply Pettit 6455/044 Metal Primer, followed by epoxy barrier coat, then Rustoleum Professional Aerosol Spray Paint,

The result is a looong lasting glossy plastic finish, even in this marine environment.

It is common for the hose clamps to each have opposite orientation, rotated 180° position.

It is useful to lap the coupling to shaft using lapping compound when disassembled.

Note, I do those same steps w/ bronze, polishing first to resemble brass.

Those parts still have a glossy plastic appearance after decades in the marine environment.

[Reefmagnet]

Originally Posted by wingless

This is from the manufacturer's data sheet.

The maximum performance of TECTYL 506 can be achieved only when the metal surfaces to be protected are clean, dry and free of rust, oil and mill scale.

Maximum performance. The cleaner the better obviously, but in all cases, imho, it works better than paint in this environment. Kind of like butyl tape vs polyurethane sealant. And just like butyl, it's no good if the part will be in contact with fuels or solvents. Best part is touch requires a spray can of the stuff and a shop rag for catching over spray