Pro Tips On Power Washing

The power washer is a ubiquitous boatyard tool, but there’s a huge difference between professional power washers and the one in your garage. And that’s a good thing. Industrial-strength power washers have the capacity to do serious damage to a boat and don’t belong in the hands of a DIY boater. Home power washers, however, have become incredibly inexpensive and widespread in recent years, so more and more often boaters are tempted to point that wand at the fiberglass and indulge in some scrub-free scrubbing. Be warned, however, that even a typical electric power washer designed for home use with a moderate 1,800 to 2,000 psi or more does have the capacity to damage Mom’s Mink.

Even relatively low pressure can rip soft goods like fabrics and upholstery, and moderate pressure can peel up decals, blast away bottom paint, and score closed-cell foam decking or painted-on nonskid – especially when used with an aggressive tip or if the wand is held too close to the material. Most medium-duty and all heavy-duty units can damage the gelcoat, too, usually by turning small cracks into big chips or crushing the gelcoat skin where a small void is present underneath.

Dos and don’ts

There’s always a certain amount of risk when using a pressure washer on a boat, but, hey, there’s some level of risk when you wash it down with a scrub brush and a hose, too. Follow these dos and don’ts to keep the pressure washing risks to a minimum.

DO follow the pressure-washer manufacturer’s recommendations for use on a car when cleaning your boat. A car’s finish is more delicate than gelcoat, so always err on the cautious side.

DON’T let the nozzle get closer than 8 inches from any surface. If you do, it can have the same effect as using more pressure.

DO wash each section of the boat individually and adjust tips accordingly. Most power washers come with a selection of spray tips ranging from zero to 65 degrees. Zero is the strongest, and the 65-degree tip is very gentle. If you’ve done the hull with a 15-degree tip and next want to clean up a painted-on nonskid deck, for example, you’ll want to stop and switch to a less aggressive tip between jobs.

DON’T start with the most aggressive tip for the job. It’s always safer to start with a weaker spray and work your way up, cautiously, if you’re not getting enough cleaning power.

DO treat all painted surfaces, including bottom paint, as delicate. Unless, that is, you plan on blasting away significant amounts of old paint. Pressurized streams have a way of quickly getting under and lifting off large chunks of paint.

DON’T allow an aggressive stream to hit delicate items like rubber hatch gaskets or canvas. Also stay away from any items that are gasketed to prevent water intrusion, like switch panels, electronics, and gauges, as well as exposed wires.

DO wave the wand back and forth slowly and evenly as opposed to holding it in one spot.

DON’T focus the stream on any section of any material that shows visible damage. Power wash a section of cracked gelcoat, for example, and you’re likely to expand the damage.

DO wax your boat with a thick, protective paste wax as soon as possible after giving it a pressure wash. You just blasted away all the old wax, and if you don’t get a new coat on that gelcoat ASAP, oxidation will quickly set in.

DON’T ever point the wand toward any person or animal.