Cleaning Bronze Corrosion

[Dino]

My new (to me) boat came with fairly green bronze seacocks and stern glands. There is a good bit if green corrosion near the top of the seacock stained cap and the caps don’t seem to be budging. I’m going to carefully try to open them with a pipe wrench.
Whats the best thing to clean them with and protect them from further corrosion?
The boat is now on freshwater so I expect the corrosion to be less in future.

 

[penfold]

Wire brush them and smear with vaseline, although on freshwater it's unlikely you'll get much verdigris appearing. If you're that way inclined you could go to town with wire wool and then brasso them, but that seems extreme.

 

[Tranona]

That is not really corrosion but a staining from salt laden atmosphere. Purely cosmetic. Clean as Penfold suggests. Although it is worse in salt laden atmosphere it can still occur away from the sea, but the vaseline will help hold it back.

 

[AndieMac]

During a slipping, I removed a verdigris stained and slightly sticking, combination seacock and strainer, and soaked it in a tub of neat vinegar for a few hours, then brushed it firmly with an old paint brush (but you could use a wire brush) and it came up as bright metal again with a very easy open and close movement.

Some are using vinegar to flush raw water cooling systems now, with great results.

 

[Dino]

Thanks folks, I got a pipe vice onto the caps on Saturday and freed them up. Then I cleaned away the corrosion and greased the threads. The brass or bronze filters are well coated in a white substance like calcium or similar. Will white vinegar remove this?
Also, should I pour some white vinegar into the seacock stack with the valve closed to dissolve any build up of krud?

 

[Whopper]

I can’t see vinegar doing any harm. You could take the 2x gauz out and clean them in a bucket. I actually suspect Cillit bang or the Lidl/Aldi equivalent would do the job very well. Another option could be to close the cocks and use a wet vac to suck up any potential debris. They’re also handy to clean any bilge water or spills under the engines than hasn’t come down the the bottom. And to give the engines a quick Hoover of any dust etc.

 

[Dino]

Good idea Whopper. I can remove them and soak them in limescale remover. Then I’ll try the limescale remover into the tubes and see if that helps.

 

[AndieMac]

Thanks folks, I got a pipe vice onto the caps on Saturday and freed them up. Then I cleaned away the corrosion and greased the threads. The brass or bronze filters are well coated in a white substance like calcium or similar. Will white vinegar remove this?
Also, should I pour some white vinegar into the seacock stack with the valve closed to dissolve any build up of krud?

I always keep a bottle of double-strength or cleaning vinegar in a spray bottle on the boat for many cleaning jobs, particularly if there is any mold developing in a damp wet locker, green algae on ropes, decks, under canopies, carpet in the winter, a great all around, very cheap to buy and you are not dealing with a chemically harsh product.