Powerwasher on fiberglass - deck & cockpit

[SV Bacchus]

My wife recently watched an episode of Zatara on YouTube and noticed they use a pressure washer to clean the deck. I think in that episode they were cleaning their sugar scoops.

She wants a pressure washer as she is responsible for the scoops! Seriously, we divided chores and she chose that one.

I know that once I used a pressure washer on plastic chairs in the back yard and totally destroyed the finish.

However I do realize boatyards use pressure washers on the bottom at every haul out. I know there is bottom paint, hopefully, under the yuck growth and they probably are not hitting the fiberglass directly.

I see one of the big box stores has a small electric pressure washer with a max pressure of 1600 PSI. I figured what the heck, how much damage can she do?

I wanted to ask everyone here the following two questions:

1. Will she, or I, damage the surface of the fiberglass?

and

2. Are we just forcing the dirt deeper into the surface of the fiberglass?

Thanks in advance for any input!

[a64pilot]

Strong ones can do damage, even to your body, weak ones don’t do much at all, in my opinion.
Try to wash a car in one of those pressure washer booths, doesn’t clean worth a Damn, but a soapy rag and a bucket does.
They are best in my opinion for places you can’t reach, like a bilge for instance.

Ones like used to clean the bottom, will cut your finger off. Many years ago I cut my foot when the recoil of turning it on made it cross over my bare foot, this was a 12 HP one though.

[fgd3]

A 1600 psi pressure washer will erode the gel coat if you hold the nozzle close enough to wash away the mold and mildew. It will look great but the surface will be more porous than previously so mold and mildew will grow back faster. You can seal the gel coat with wax but that won't last. Pressure washing is best used as a preparation step prior to painting.


Fabbian

[JamesPNW]

The Fiberglass strength is 30,000 PSI, typical water pressure washer is less than 3,000 PSI. Unless the pressure washer can get closed to the Fiberglass PSI strength it cannot cause any damage. IMHO

[Zzmeyer]

Keep away from teak and sunbrella. Destroyed both.

[ggray]

Originally Posted by Zzmeyer

Keep away from teak and sunbrella. Destroyed both.

Yes!!

[ranger58sb]

We have an electric pressure washer at home, and I've used in on the boat a few times... works OK, no damage. Kind of a pain in the neck to run the electric rods forward when I take the thing up to the bow...

Recently I've heard there's a battery powered one on the market, Worx brand... and if it actually works OK as a pressure washer it would probably be less fiddly. I've got a Worx battery-powered leaf blower at home, several years old by now, and it works for my purposes way better than a gas powered blower... so I'd guess the "battery powered" part about a pressure washer could work OK.

-Chris

[Spot]

Pictures of my boat:
1-as received
2-during washing
3-pressure washer itself

Before the pressure washer I swept and sponged with soapy water which removed most of the lichens and made it look more like the dark side of the second picture. I cannot remember which tip I used but it was not that difficult to get it clean even with the old, non-maintained gel coat.

[slug]

Originally Posted by SV Bacchus

My wife recently watched an episode of Zatara on YouTube and noticed they use a pressure washer to clean the deck. I think in that episode they were cleaning their sugar scoops.

She wants a pressure washer as she is responsible for the scoops! Seriously, we divided chores and she chose that one.

I know that once I used a pressure washer on plastic chairs in the back yard and totally destroyed the finish.

However I do realize boatyards use pressure washers on the bottom at every haul out. I know there is bottom paint, hopefully, under the yuck growth and they probably are not hitting the fiberglass directly.

I see one of the big box stores has a small electric pressure washer with a max pressure of 1600 PSI. I figured what the heck, how much damage can she do?

I wanted to ask everyone here the following two questions:

1. Will she, or I, damage the surface of the fiberglass?

and

2. Are we just forcing the dirt deeper into the surface of the fiberglass?

Thanks in advance for any input!

Very useful tool

It cleans and conserves water

Just remember that it’s powerful and can destroy things

Don’t work close up and attempt to blast something clean

Don’t close blast fabrics , don’t close blast teak




Buy the cheapest , lightest power wash and fit it with an extra long high pressure hose

[SV Bacchus]

Thanks all, great input. I will advise the crew on how to operate the unit in a way to not damage the surface.

$119 and 1600 PSI was the cheapest and weakest electric model I could find so we are good there. And it is a Ryobi for that price. I've had good look with their tools..

[singlespeed]

The age and condition of the gel coat will dictate the effectiveness and potential for damage. Power washing stress cracks in the gel coat, while frequently harboring dirt and mold, can also lead to breaking or lifting of the gel coat. Proceed with caution.

[sailah]

I use my 4000PSI Honda powered pressure washer in the Fall during haulout and during the Spring commissioning. I use a wide tip and am careful to not blast the woodwork. On the nonskid it works great. Nothing else seemed to work as well. Been doing this for last 5 years with no signs it's causing an issue.

Like any tool, it can either be a huge timesaver or make a big mess. Just don't point blast anything and you should be fine. I also stay away from deck fittings or anything bedded as I don't want to blast water up under those.

[CarlF]

I have a mini power washer that I bought off Amazon for about $75 that I use on the decks. It says its pressure is around 800psi when running - far less than the boatyard units. It's perfect to blast dirt and bird doo out of nonskid and clean all the funny corners on deck like around stanchions. It's not up to cleaning a bottom.

It's very small - I store it and the hoses in a milk crate in a cockpit locker. Runs off the inverter and uses only 1.5GPM. I just connect it to the boat fresh water system if I'm not at a dock. It uses much less water than a hose and hand sprayer. I've thought about hooking it to the salt water wash down but haven't tried.

At $75 I expected it to last less than a year but it's still going fine. They say it has a three year warranty but I haven't needed to test that.

https://www.amazon.com/Sun-Joe-SPX20...b_title_garden

[jooa]

I have the same Ryobi 1600 psi power washer and find it does a great job of cleaning the boat. The 1600 psi is no too strong to damage the fibreglass, but as others have cautioned, don't get too close with the tip, don't try to power out stains, be wary when near fabrics, etc. all excellent advice.

A couple features I like about the Ryobi is it does not have wheels. This is good because I wash my boat at the dock and the last thing I need is for it to roll off the dock while I'm busy cleaning. It is small and compact which keeps it stable and highly unlikely to tip over, also makes stowage onboard easier.

With a nod to those who think the power washer can damage the fibreglass, I don't use my power washer every time I clean the boat. I use it for the first washing of the season to get out the dirt and mildew and then maybe once later in the season. Otherwise I use soap and a deck brush the rest of the time...no need to anger the fibreglass gods especially with a 44 year old boat.

One other word of caution, be aware of what angle the water jet is in relation to deck fittings, toe rails, stanchion bases, etc. Keep the angle so that it does not blast out chaulking from beneath the fittings. I have heard of people who get too zealous in their cleaning and have cleaned the chaulking right out from under the fitting.


OH, and always wear boots or shoes when power washing, 1600 psi can cause injury to flesh.

[waterman46]

Our boat had a deck non-skid finish that attracted dirt. Could not get it out except by wire brush which was very tedious. Tried a power washer and it worked very well to get the dirt out, but it did lift a couple of one-inch size spots of the gel coat. Maybe there was already a small crack in those places.