All this talk of leaking toons got me paranoid and..........

[The_Hellbilly]

FOUND THE LEAK!!! It was in the weld I circled. All the dealer did was screw the fitting in (see the arrow), hook it to a compressor, and start spraying it with soapy water. The good news is that it is under warranty

[badmoonrising]

Nice and good that they took care of you.

[WaltF]

Guessing here...
That plug stamped 302.

Might that be the type of Stainless Steel?
http://www.upmet.com/302-mechanical.shtml

[The_Hellbilly]

Just picked the toon up from the dealer. Here is the after pic. Voyager picked up the tab.

[GregF]

They need a better welder.

[The_Hellbilly]

I thought it was a bit sloppy also. If I could have welded it with my arc welder I would have. I never learned how to mig/tig weld.

[GregF]

That really looks more like MIG than TIG. It should still work if he got that hole he blew out in the back, filled in OK. It is good the dealer did it in case you are going back for more warranty relief.

[georgiatoon]

Never, ever use brass or anything else but stainless...trust me. Some dumb ass used brass hardware on my old Starcraft and that was the reason why there were holes in the transom. He used brass hardware to install the transducer bracket and the hull was swiss cheese behind it. Aluminum plug would go in and never come back and plastic gets brittle fast.

"Aluminum and brass just add water and you have a battery" Not good!

[georgiatoon]

FOUND THE LEAK!!! It was in the weld I circled. All the dealer did was screw the fitting in (see the arrow), hook it to a compressor, and start spraying it with soapy water. The good news is that it is under warranty

Someone said on this post something about how easy welding was - That's why shit like this happpens crap weld by want to be welders -" Six months in school and your a pro". Thirty plus year experience and still learning

[cbavier]

Mine are Brass tapered plugs. I used Teflon tape on the threads. I took the plugs out every fall at the boat ramp when I brought the last pontoon home to winterize it. That away any water in the tubes can drain out. My toon stays in the water all summer. Though last summer was my first year to own this boat. The previous owner kept the boat in a Lake from May till October. When I took the plugs out both tubes had water in them so the boat will be going to a welding shop next Spring.

[JohnO]

Aluminum will corrode when exposed to stainless in a salt environement.

Please see the linked Galvanic series table
http://corrosion-doctors.org/Definition ... series.htm

The further two metals are from each other the worse the corrosion will be (of the anodic or less noble metal).

I work for the navy and we do not use stainless of any sort in contact with Aluminum. (with the rare exception of in interior spaces via a bimetalic pad.)

BMR, I think you've just been very fortunate or your Stainless is not in direct contact with the aluminum.

One thing that the table doesn't address is the oxidation of the Aluminum. Apparently the aluminum oxide layer is pretty non-reactive. Also, the use of a stainless bolt (for example) in a large aluminum structure spreads the galvanic current out over a large area which should result in less (or less severe) corrosion.

Please note that I'm an electrical, not a materials guy, but that's what my reading of the specs etc leads me to.

[cbavier]

Aluminum will corrode when exposed to stainless in a salt environement.

Please see the linked Galvanic series table
http://corrosion-doctors.org/Definition ... series.htm

The further two metals are from each other the worse the corrosion will be (of the anodic or less noble metal).

I work for the navy and we do not use stainless of any sort in contact with Aluminum. (with the rare exception of in interior spaces via a bimetalic pad.)

BMR, I think you've just been very fortunate or your Stainless is not in direct contact with the aluminum.

One thing that the table doesn't address is the oxidation of the Aluminum. Apparently the aluminum oxide layer is pretty non-reactive. Also, the use of a stainless bolt (for example) in a large aluminum structure spreads the galvanic current out over a large area which should result in less (or less severe) corrosion.

Please note that I'm an electrical, not a materials guy, but that's what my reading of the specs etc leads me to.

So JohnO is it ok to use Brass with Aluminum tubes and do you think they are really pure Brass anyway? I wouldn't know if the plugs that I have are the originals (1982) or not but I would assume they are. I surely wouldn't think any pontoon manufacturer would put plugs in a new pontoon that would harm the aluminum.

[JohnO]

So JohnO is it ok to use Brass with Aluminum tubes and do you think they are really pure Brass anyway? I wouldn't know if the plugs that I have are the originals (1982) or not but I would assume they are. I surely wouldn't think any pontoon manufacturer would put plugs in a new pontoon that would harm the aluminum.

Again I'm not a matrials guy. Brass is closer to Al than some stainless. It kind of depends on what Aluminum Alloy they are using and what stainless they were using.


The first thing I'd do is ask the manufacturer what they recommend. They should have had a good materials engineer look at it already.

[GregF]

I went to Mercury for an answer about using brass sending units in aluminum blocks and the short answer was "no problem".

[cbavier]

I went to Mercury for an answer about using brass sending units in aluminum blocks and the short answer was "no problem".

But Greg we're talking about Brass Drain plugs on pontoon tubes not Aluminum Engine blocks. I'm sure engine blocks even if they are aluminum are a lot different than thin toons and never exposed to heat like an engine block is. It might be the same but I doubt it. I'm sure aluminum Engine blocks are some kind of special heat treated. Somebody else jump in here.