Somehow, your neighbor’s 15-year-old boat looks showroom new. How? Elbow grease, my friends. Elbow grease. But, for me, that work doesn’t include lugging a bucket of soapy water around. Here’s how to wash a boat the right way.
Wash
Most boat soaps suggest several ounces of soap per gallon of water. That gets a good suds going and, when applied with a sponge or soft brush, does a good job of lifting dirt. It also does a good job of wasting soap.
A utility spray bottle from a discount or hardware store costs a couple of bucks or less. It’s better to use the soap concentrate straight if the spray bottle will pump it, but you might have to dilute the soap. This bottle from Walmart sprayed Blue Coral soap straight. Some boat soaps are of higher viscosity and are apt to need watering down. Start with 2 parts soap and 1 part water. A soap that won’t hurt your car finish won’t hurt your boat.
Hose down the area of the boat you want to wash, rinsing away loose grime, then shoot a few stripes on it with your spray bottle. Brush it in, and swirl it around. The more-direct application of soap adds emulsive dirt-lifting power. When you’re done, rinse it away.
![How to wash a boat: Supplies on the deck](jpg/btg0421-qst-washing-1024x683.jpg)
Swab the Deck
There is no substitute for a good deck wash on a nonskid deck surface. Star brite’s Deck Cleaner (about $25 per gallon, westmarine.com) is my go-to. In comparative tests in BoatingLAB, it has cleaned wine, grease and fish-blood stains better, and kept subsequent spills from staining the deck. It contains PTEF, a chemical considered a hazard in California, but it offers a sealing effect on diamond-pattern nonskid.
Once the boat is washed, spray the cleaner on the deck, brush in, rinse, then spray and brush again, but let the cleaner dry in place.
Details
Use a detailer spray to wash the dashboard, consoles and compartments. Make sure the spray sports a UV protectant. There are plenty of good ones, but I lean on Lucas Slick Mist Marine Spray Wax ($8.99, amazon.com). To keep it off of tempered glass, spray it on a microfiber cloth and wipe the dash. It does a nice job of cleaning acrylic windscreens, so direct spray is A-OK. Wipe it dry with a microfiber cloth.
Upholstery
If your boat upholstery is fishy with blood and slime, use the spray-soap-and-hose approach, but then wipe it down with a vinyl cleaner and protectant that has a strong track record like 303 Marine Protectant ($19.99, westmarine.com). Wipe it on, leaving a film in place to dry and seal your vinyl.
Brushes
West Marine makes brushes that float on an interchangeable extendable handle. Use the blue soft brush on the hull and interior, and the yellow medium brush on the bottom and nonskid deck. The white coarse brush is for stubborn spots and waterline stains (from $40, westmarine.com).
About Wax
In BoatingLAB, we tested several waxes, including two automotive waxes: One was tinted green; one was beige. Both left our white gelcoat with a matching patina that was hard to remove. On the other hand, we had good results with car waxes that were untinted.
FAQ
Can I use Dawn to wash my boat?
While Dawn dish soap can be used in a pinch to wash your boat, it is not recommended for regular use. Dawn contains degreasing agents and other harsh surfactants that can strip away the wax protection and dull the gel coat over time if used frequently.
What happens if you don’t wash your boat?
Failing to regularly wash and clean your boat can lead to several issues like accelerated oxidation, fading and chalking of the gel coat’s color. Additionally, salt buildup from saltwater boating can cause corrosion on metal parts, fittings, and hardware if not properly rinsed.
Do you need special soap to wash a boat?
While not strictly necessary, using a dedicated boat soap or wash is highly recommended. These products are formulated specifically to be gentle on gel coats and wax protection while effectively removing salt, grime, and environmental contaminants.