Brass to aluminum, problem in salt?

What about brass screws and hardware on an aluminum boat that may see some brackish water at times and even less of the time, full salt, but mostly fresh. The boat has some brass already on it that looks to have been there for decades and I see no problems, but I don't think it has ever been in brackish or salt water.

m casey stock said:

What about brass screws and hardware on an aluminum boat that may see some brackish water at times and even less of the time, full salt, but mostly fresh. The boat has some brass already on it that looks to have been there for decades and I see no problems, but I don't think it has ever been in brackish or salt water.

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Look at answer to jeffery ? about 3 down from yours Go to site I added it may clear up some things..cva34

m casey stock said:

What about brass screws and hardware on an aluminum boat that may see some brackish water at times and even less of the time, full salt, but mostly fresh. The boat has some brass already on it that looks to have been there for decades and I see no problems, but I don't think it has ever been in brackish or salt water.

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In salt you will see problems. I saw it happen over a week long salt trip, after it had gone for who knows how long in freshwater without the slightest concern.

I have just recently read where people in FL are using brass nuts on SS bolts with aluminum backing to mount small (5-25hp OB's) on small fiberglass boats/microskiffs, etc. Aluminum was used in backing/support plates, jackplates, etc., thru FG, with brass nuts to avoid (?) corrosion on those mounting bolts.

TNtroller said:

I have just recently read where people in FL are using brass nuts on SS bolts with aluminum backing to mount small (5-25hp OB's) on small fiberglass boats/microskiffs, etc. Aluminum was used in backing/support plates, jackplates, etc., thru FG, with brass nuts to avoid (?) corrosion on those mounting bolts.

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To avoid galling the threads. Larger diameter stainless bolts sometimes gall before tightening adequately, which is why brass is used. It's a balancing act, all the way around. :lol:

Proper galvanic protection also plays an important factor in the degree of corrosion. I recommend any aluminum boat that is used in saltwater have a zinc anode mounted to the hull.

PSG-1 said:

Proper galvanic protection also plays an important factor in the degree of corrosion. I recommend any aluminum boat that is used in saltwater have a zinc anode mounted to the hull.

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BINGO!

Wow! Thanks Guys for the quick and informative responses. I'll be sure to read the link that cva34 left on the other thread. Most of the brass machine screws will be pained over, so hopefully they will be sealed and stay protected, but the boat came with these real old brass cleats and I plan to polish them until they blind! LOL :LOL2: I was wondering then if I should make some plastic insulators to go between the cleat and the boat and the attaching nut and the boat? After reading the post I think I'll just be safe and make some. thanks again