Design & DIY

Cottage Q&A: Cleaning pontoons

By Mark Herreid/Shutterstock

I have a 10-year-old pontoon boat. The pontoons are dirty. What can I use or do to bring back the lustre of their original shine?—Wes Green, Meadow Lake, Sask.

Their original shine? That may be unrealistic, especially if you haven’t cleaned them in a decade. “Pontoons are tough because they stain and oxidize over the years,” says Sean Horsfall, the owner of Len’s Cove Marina in Portland, Ont. “It’s very hard to make them ‘new’ again.”

That said, he recommends pressure-washing to get rid of as much loose surface grime as possible, then washing the pontoons with an aluminum-specific cleaner. There are plenty of brands; check marine retailers. Follow the product’s application instructions carefully. “Some of these chemicals are strong,” says Horsfall. You’ll need skin and lung protection, “and be aware that the products can damage the paint on boat trailers.” 

After an aluminum cleaner, Mitchell Wolfe, with North American pontoon boat-maker Bennington, recommends following with an aluminum polish, then buffing (you can use a car buffer). “Boat ‘fouling’ is natural when water meets aluminum,” he says. “But you’d be surprised how much buffing can help restore it.”

If you want a gentler, greener option—and for the sake of the environment, we’ll always recommend that—you can mix a mild dish detergent, such as Dawn, with water, says Wolfe. Use a sponge, a soft-bristled brush, or a one-gallon sprayer to clean the pontoons—well away from the lake, of course. 

Let’s be real: dish soap and water (or baking soda and water, or vinegar and water, or magic and water) won’t remove stains that have built up over years. If shiny pontoons are really important to you, and you don’t want to deal with scary, paint-stripping acid washes, take the boat to a professional.

“We do this job with a forklift,” says Horsfall. “And respirators for the staff.”

This article was originally published in the March/April 2022 issue of Cottage Life magazine. 

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