Strainer Question

[Stinkpot]

I've had this strainer below on my Calvin Beal for 5 years now. After the 2nd year, I had to drill out the threads in the bronze body and re-tap them for larger screws because they were "stripped". Turns out the bronze body was succumbing to the effects of galvanic corrosion since the stainless screen is fastened to the bronze body with stainless machine screws. Now, I have to drill & tap 8 NEW holes in new locations because the original holes enlarged so much that I can't go any bigger. I dunno, seems like a poor design to me. Why wouldn't they have used SiBr screens and screws? Has anyone else noticed this with this type of strainer? If I switch to SiBr screws, all I'll be doing is changing the dissimilar metal interface to the screen-to-screw points; won't that cause the SiBr screws to waste away? What if I used maerlon screws and ensured a thick coat of paint on the surface between the screen & body? Any other ideas? Thanks.
Stinkpot

 

[Pedlyr]

When I work with aluminum and steel or other dissimilar metals I usually make a galvanic isolator out of vinyl plastic or rubber. Like a gasket. Especially on aluminum boats with steel sea chest valves.

I also use something called Penetrox on all my hardware which will not eliminate galvanic corrosion but slows it down. When I was fishing, used it on the deck plates/hatch dogs when I rebuilt them. Sometimes there was wet steel, lead, aluminum or bronze components bolted together. Depending on the make.

I like to use Penetrox on my wiring as well. I thought at first it might promote galvanic corrosion because it is for conductors. But it seems to help. Probably cause it displaces moisture.

Penetrox A Aluminum Copper Anti Seize Seez

 

[tunafishhkg]

I always use TEFF gel when using SS with ALUM that is made to stop this problem. Great stuff especially on my reels,outriggers ect.

 

[Stinkpot]

Well I made up a gasket to fit between the bronze strainer housing and the stainless screen and I'll switch to bronze machine screws to hold it in place; we'll see what happens next season.

Thanks!

 

[BillD]

My 1996 31 Blackfin has the same intake scoops.

When I bought the boat in 08 had to remove the screens.

S Florida boat in water year round 11 seasons.

Tremendous growth over the scoops and metal ware.

Surprising, no issues removing the SS screws.

I've had the screens off a couple of times.

FWIW,

Bill D

 

[El Mar]

Is that strainer tied into your bonding system??

Maybe put a zinc on it somehow?

 

[Blacktide]

I have a zinc on the aft side of the scoop on mine. No serious corrosion on it at all

 

[traditions]

second the zinc,drill and tap on the back side.We dont see many of that type strainers,mostly the one piece cast bronze ones.I think they are designed to go on rond side forward,but very rarley see them that way,mostly put on like a scoop.

 

[jerseysportfisher]

I have Buck southbays as well, B&S southbays actually come with zincs, but the through bolt pattern doesn't line up with the bucks, so I just used their zincs, drill and tap

B&S Strainer Zinc - Strainers- Doka- South Bay - Other Anodes - Zinc Boat Anodes