2019 SC25 sports tower corrosion

[billchips]

Hi, I just wanted to tell you I now have a 2021 R8 Outboard model with the Sports Tower Arch. It is experiencing the same corrosion problems in the same areas. All mounting screws holding on the chrome fittings are totally rusted. Exactly same corrosion. After showing photos to the dealer and him forwarding to Cobalt, did they now say they will replace the arch as a warranty issue. Currently it is on order and once it arrives, they will swap it out. We all spend a lot of money for these boats today, and it should not happen in such a short period. Hope you got yours fixed. Bill

[Tgarris]

Bill not to be a pessimist but most of us waited 8-10 months mostly due to the delays from the tower company blaming “supply chain” issues. My suggestion is to be a squeaky wheel. Cobalt immediately should switch to fiberglass towers. I am not going to buy another Cobalt due to this issue. Btw not uncommon with other boat Mfr’s as well, powder coating an aluminum tower just doesn’t work.

[jhnmdahl]

This isn't a super common problem, and I'm curious if the aluminum arch was anodized, or if there were flaws in the anodizing contributing to the corrosion.

If Cobalt's tower was fiberglass, I'd probably go aftermarket for mine and find a Samson or something else similar to what my boat has. Are there any major manufacturers out there making fiberglass towers?

A better solution might be to pay more attention to galvanic isolation between dissimilar metals, or bite the bullet and go 316 stainless for corrosive environments (i.e., saltwater).

[Tgarris]

Yes agreed to go 316 stainless completely with no powder coating. yes companies like Regal use fiberglass. I’m not convinced corrosive environments has anything to do with it, I believe you are correct with the dissimilar metals and the process Sampson is using. Sea Ray has similar problems with the same process with powder coating the aluminum towers and have had to replace as well. These towers look nice but geez the keep it simple Bimini is so much easier and less aggravating imo (I do prefer a tower for the looks and usefulness however). First world problems

[jhnmdahl]

yes companies like Regal use fiberglass.

I looked at a bunch of models on their website and only see a few metal towers with fiberglass or composite covers. Do you know which boat(s)? A quick Google search also didn't find any fiberglass wakeboard towers. Fiberglass (or FRP) isn't great at resisting flex or bending and seems a dubious material choice for something like a wakeboard tower, so I'm interested if someone has found a way to make a viable one.

I’m not convinced corrosive environments has anything to do with it

No, the saltwater is a much better electrolyte than fresh water, and is a huge factor in the problem. Fresh water is a pretty weak electrolyte, and galvanic corrosion is so slow that frewshwater boaters often don't replace sacrificial anodes or notice any real degradation over the lifetime of their boats. If there's no electrolyte at all, you can leave dissimilar metals touching essentially forever with no corrosion.

Yes agreed to go 316 stainless completely

This is a great choice for a saltwater environment, and should hopefully put an end to your issues so you can focus on having fun with your boat!