Beneteau aluminum toerails stain hull

[carlylelk]

I have a 1989 Beneteau 285 with aluminum toerails. For the past 7 or 8 years I've been getting hull stains that originate at the holes in the toerail. It seems to me that the aluminum is slowly corroding and the corrosion product is what is staining the hull. Within a month of polishing the hull, the stains are back.

What have others done to stop this? I thought of painting or sealing the toerail, but hate to start that.

[boatman61]

Originally Posted by carlylelk

I have a 1989 Beneteau 285 with aluminum toerails. For the past 7 or 8 years I've been getting hull stains that originate at the holes in the toerail. It seems to me that the aluminum is slowly corroding and the corrosion product is what is staining the hull. Within a month of polishing the hull, the stains are back.

What have others done to stop this? I thought of painting or sealing the toerail, but hate to start that.

Have you put an electric meter to it to see if its live... had that on my Bendi... turned out some wire to the bow nav lights had chaffed and it was rotting my ally... and making yellow stains on the grp.

[carlylelk]

Originally Posted by boatman61

Have you put an electric meter to it to see if its live... had that on my Bendi... turned out some wire to the bow nav lights had chaffed and it was rotting my ally... and making yellow stains on the grp.

I'll give that a try, but most older Beneteau's in my marina seem to have the same problem.

[GeoPowers]

Originally Posted by carlylelk

I have a 1989 Beneteau 285 with aluminum toerails. For the past 7 or 8 years I've been getting hull stains that originate at the holes in the toerail. It seems to me that the aluminum is slowly corroding and the corrosion product is what is staining the hull. Within a month of polishing the hull, the stains are back.

What have others done to stop this? I thought of painting or sealing the toerail, but hate to start that.

You don't say what color the streaks are but I am guessing black? Yep, it is a pain in the ass, but simple fix. First clean the toerail and then
then spray Corrosion-X (or similar) onto a rag and rub it onto your aluminum surfaces. This includes the toerail of course but also the boom (if Al like mine) which also contributes to the streaking to a lessor degree. If you treat the boom be sure to get the Corrosion-X into the groove along the top of the boom, that's the part that gets the most exposure to water. The Corrosion-X lasts about 4 months before you need to re-apply. Or just say screw it and live with the streaks.

Frank

[GordMay]

Likely, it's atmospheric dust, dirt, & contamination, not corroding aluminum rails.

Wash & Wax ➥ Combating Black Streaks Article - Protect All

[svHyLyte]

Originally Posted by GordMay

Likely, it's atmospheric dust, dirt, & contamination, not corroding aluminum rails.

Wash & Wax ➥ Combating Black Streaks Article - Protect All

If you live in an area where there is a lot of diesel truck traffic or another nearby source of airborne soot, particulates will accumulate on your decks, much of which will include sulphur compounds. These, coupled with the moisture in the air, will combine to create a mild but detectable acid that will erode gel coat and the surface of aluminum. Add enough moisture, i.e. rain, and the resulting debris washes through the toe-rails and drips down the hull causing streaks. This is/was a particularly bothersome problem when we had our boat at the Alamitos Bay marina in Long Beach, Ca. with the nearby highway (to say nothing of the typical airborne pollution in LA County). The only "fix" was frequent wash downs and waxings. We see much less of that here in southwest Florida where our marina is remote from major traffic and there is little air pollution.

FWIW...

[carlylelk]

Thank you all for the help! I'm going to try the Corrosion-X first.