Best rust prevention for iron jack shaft

[Rodd]

I have a v-drive with a 4 foot jack shaft connecting tranny to v-drive. Stuffing box is directly below uncoated iron jack shaft, approx 1 inch in diameter. Due to spray from the stuffing box while running, part of the jack shaft has rusted away a bit. I cleaned this up on a wire wheel, and am wondering the best way to protect the shaft so that it doesn't start rusting again.

What comes to mind immediately is priming and spraying with rustoleum. Any other suggestions?
Thanks!

 

[kloudie1]

Rustoleum primer followed by an epoxy overcoat to keep water out..
Another option might be to install a shield (attached to boat , between the stuff box and the jackshaft) made of something like 1/8" clear Lexan on plastic brackets so it can be easily "snapped" into place and removed.

 

[wufibugs]

POR 15

 

[uncledom]

POR 15

 

[kloudie1]

The POR looks like great stuff.. I've not personally used it .. Looks like they've done their homework ..

 

[Rodd]

Thanks guys- I briefly looked at POR 15 on the web. Now that I have wire wheeled the shaft clean of any remaining rust would I need to use any of the other cleaners or preps or just apply the POR 15 directly to the shaft? After applying I could then spray with rustoleum? or just leave it alone ?

 

[uncledom]

Becareful. Whatever this gets on it sticks to until it wears off. The shaft, your skin, the boat, whatever!

 

[wufibugs]

Uncle is right. Once it begins to dry, you can only sand it off or try a little Composition C-4. I am unaware of any chemical remover that will take it off. After you wire brush, I'd wipe down with acetone. Rust is relentless and counterattacks almost immediately so you want to apply the POR as soon as the acetone is fully evaporated.

 

[CloudDiver]

PO15 is supposed to chemically bond (bond, chemically alter, & seal) to rust. The substrate dos not have to be completely free of rust which is nearly impossible for cast iron or other very porous metals. I haven't used it in a long time, but I remember the instructions saying to removing loose and flaking rust as much as possible, but light surface rust actually helps it bond better. I used to paint the interior sheet metal and roll cages of rally cars with PO15, when you do it right it looks as smooth as powder coat when dry and its nearly indestructible.

 

[Justin_NSA]

POR should work on an iron keel then I assume. Next time I haul Bella out I may use it before recoating with bottom paint.

 

[wufibugs]

Their FAQ is very helpful. You will have remove all the paint from the keel down to the metal before you apply POR 15. It should receive a topcoat of bottom paint.

 

[Newport Bob]

Use it on my iron keel areas and spots rusting thru bottom paint

 

[Gunni]

I could never find any manufacturer or qualified pro recommendation for use of POR 15 on an iron keel. It isn't waterproof. The builders use high solids two-part epoxy primer. So that is what I repair with.

 

[CloudDiver]

Gunni makes a good point... I'm not sure I would recommend it for iron keels. From a pure scientific point, having used PO15 and knowing how it bonds to rust, you could use it on the keel just to seal it. You would still have have to sand and topcoat it with epoxy barrier coat and then bottom paint.
When using PO15 on cars and such they specify that it does fade in UV so they do sell their own brand of topcoat, but you have to sand first. Technically any top coat would work. With that said, on a keel, you'd be better off sand blasting and then using Interprotect 2000 or the Petit epoxy barrier coat. Those epoxy primers bond tenaciously to metal, especially a sandblasted surface.

 

[centerline]

zinc chromate primer... it and be found in a spray cans, pints, gallons, ect... it bonds perfectly to clean metal and prevents rust and corrosion.... without encapsulating the object, about the only thing that is better for preventing rust on steel is a hot-galvanize....