Stainless Chimney Rust Spots

[Tsehum Pete]

My Dickenson diesel stove has a chimney which extends about 14 inches above the coachroof. The chimney must have been made of a poorer quality stainless steel. Every couple of months I polish it up so it looks like new, then within a short while rust spots appear again. I do not have this problem on all the other stainless parts on the boat, only this chimney. Is there some way to seal the metal after getting it spotless so I can keep it looking better longer?Pete

 

[Ross]

You might try passivating it with dilute nitric acid.

Some SS will show rust but not as severely as low alloy steel.

 

[Landsend]

why not paint it with flat black BBQ paint?

nm

 

[KennyH]

I would recomend something called lecton oil.

I have used a product from colony paints I believe called lecton oil. Not sure if spelling is right. It is basically a tung oil with better sealing properties. I have seen it keep a brass bell from turning for about 3-5 years. Best sealer I have found for marine environment. Never used it on stainless. It is designed to be a wood sealer but works for other items.

 

[KennyH]

One other thing I have done.

I had some bad stainless steel from Cheoy Lee and they recomended an acid bath in hydrocloric acid. It didn't fix them permanently but seem to improved the constant cleaning with powdered cleaner like comet. Maybe as they aged they just quit rusting as bad, who knows.

 

[sailaway50]

Rust on stainless

Recently brought boat from FL to OH, and would like to clean rust off the SS. Previous thread mentioned hydrocloric acid, where do I get this and does anyone else have any suggestions.

 

[Ross]

I know that it is a jump from boats to swimming pools

BUT after several minutes of searching the web I found this site and the advise fits what I have learned over the years.http://www.recreonics.com/fyi/stainless_steel_maintenance.htm

 

[Tsehum Pete]

A Good Waxing

Thank you for the link Ross and to others for the helpful suggestions. Maybe the previous owner used steel wool at some point. Looks like several coats of a good wax after cleaning might solve/minimize the problem. Will give it a try next week when I finally get out to the Coast to the boat.Happy boating folks, Pete

 

[Eddie7045]

Stainless is more accurately caled "corrosion

resistant" steel and comes in a variety alloys, some more resistant to the effect of salt water than others. Manufacturers using the better stuff generally are quick to note the alloy used. In other cases the word "marine" stamped on a hose clamp, for instance, indicates use of a 300 series alloy as opposed to the less corrosion resistant automotive clamps. Swimming pool acid can desolve rust and then be rinsed off from stainless or even cold rolled steel prior to putting on or reapplying paint or other protective coat, or just to remove spoting from stainless items left bare.

 

[SamLust]

It's the Heat

Your chimney gets way hotter than any other piece of stainless on the boat. Look at the first bend on chromed exhaust pipes comong out of a motorcycls's engine. You'll see colors ranging from slight yellow to deep blue. Nobody in motorcycling has found a way to stop bluing of pipes either. (Aside from not running the engine.) About the only thing you can do is to keep the stainless as clean as possible, free of wax and any other sort of preparation. They are what start yellowing first. And as Landsend said, if you can't deal whth the natural phenomenon caused by the heat, then paint it black. Maintenance then will consist of an occasional shot with a spray can.