Powerwashing Gelcoat?

[Jmreim]

saw a dock neighbor powerwashhing his entire trawler above the hull (flybridge, decks, sides, ceilings, etc). He was using an electric Cat 1800 psi washer and while the job seemed pretty effortless and the results were terrific from a distance, is this safe for gelcoat? Don't think I've see that done previously and before I try it myself, thought I'd check-in with the TF experts.
Thx -
Jim

 

[Greg QS]

NO No No , It can be done but really easy to damage gell coat. Way too easy to abrade the gelcoat, Especially the old stuff. You should see wat a pressure washer does to concert.

I guy did that in my marina. Looked great and clean. It will never shine again no mater how much wax is applied. Gave him a nice matt finish. The new dirt sticks like glue too.

 

[PM]

If you must pressure wash your gelcoat, buy a cheap, low pressure electric power washer from Harbor Freight. Like 1,500 psi or less. Never use your gas powered washer, 2,500 +psi on gelcoat. It will look awful in a year.

pete

 

[Shrew]

I think the discussion is somewhat moot unless you're including which spray tip is being used. I'd be very surprised to see a 40 degree (white) or a 65 degree (black) do damage, especially if used at a sufficient distance away.

Yes, at 1-2 inches using a 0 degree (black) tip I could probably etch my name into concrete.

Also 1800 PSI (probably more like 1500 real numbers and less if there is any head, isn't terribly powerful.

 

[rslifkin]

I don't like using a powerwasher above the rub rail personally. Using a wide angle tip at a decent distance you probably won't hurt the gelcoat, but I'm always concerned that it's too easy to blast sealant out from under fittings, etc.



That said, I see people powerwashing their boats frequently. I'm one of the few in our marina that only ever scrubs the deck with a brush, it seems.

 

[Hippocampus]

Other issue is bedding and sealants. They tend to not like power washing.

 

[DDW]

There is nothing wrong with the right power washer on gelcoat, intelligently used. You can do damage with any tool, even a brush, if unintelligently used.

 

[kthoennes]

Yep, same as the other posters -- I'm badly neglectful with buffing and waxing the gelcoat above the waterline on our boat, and I do use one of those common, Coleman gas powered pressure washers, but I use a wide tip and keep some distance. I just power wash to clean off the dirt, cobwebs and spider marks, bird droppings, dirty footprints on the horizontal surfaces, and hose off the white powder. You use the wrong nozzle or get too close and you do bad things -- like blast off the cleat bedding, or force water into places it shouldn't be.

 

[Delta Riverat]

I've used this Harbor Freight cheapie electric on my boat with good effect. But I'm going to modify use to just pre-wash and rinse.

Get her wet and then brush on the rainx carwash mix with a 12 inch soft brush on an 8 foot painter pole, then rinse off with the power washer. The cool thing about pressure washers is you can get everything wet without using a lot of water.

The cool thing about the rainx is I've tried it and it really does dry spot free. My new go to for washing windows on the house too -

 

[koliver]

I have always been leery of the forces exerted on gelcoat by a powerful blast of water. I don't have any but my own evidence, but I wonder if the advent of power washing coincided with the emergence of blistering in gelcoat.
I am careful to do my own power washing and keep the nozzle only close enough to clean.
I have had blisters on my sailboats, but so far, not on my present boat and I want to keep it that way.
Above the waterline, letting things go so that you might be tempted to use a PW is way too long between cleanings.
On a teak deck, a PW will do damage very quickly, not only blowing out the black caulking, but also abrading the teak itself.

 

[Comodave]

I had a center console that I used a power washer on regularly but it was a roto cast boat. It was 22’ and virtually indestructible. The main problem with it was that the plastic had tiny pores that would trap dirt and scrub all you want it wouldn’t come clean unless you had a power washer and then it cleaned up great. It was a tough boat, I have hit it as hard as I could with a sledge hammer and did no damage. Wish I still had it but my wife said no to 3 boats at the same time so it had to go…

 

[Delta Riverat]

I agree. Get too close with the nozzle adjusted wrong and it leaves a mark.

That's why I modified my approach to just wetting and rinsing and do the cleaning with the bucket and the brush -

 

[Aurora53]

I’ve been using an electric power washer with a wide tip. After wetting area I use a foam cannon then a soft scrub brush with an extendable pole.
The foam cannon spray a thick layer of foam then I scrub and rinse and move on to the next section.

I picked up the technique from a car detailing guy. Lots of different soaps can be used for different purposes. On my last boat I used the awlgrip soap and it worked great. The foam cannon costs about $25

I don’t have a picture of me using it with the boat but, this is what it looks like on my car.

 

[thataway]

I have also been using a foam cannon, and "low, high pressure"--plus a brush from Ryobi. There are a number of different soaps such as Chemical Guys (now at our local Walmart) or one of numerous other brands, including the major wax/detailing products and Rain X as above, for use in the foam cannon. I use the portable 18 volt battery Ryobi operated 325 PSI pressure washer, as pre rinse, then after the foam sits for a few minutes, I use the long pole Ryobi brush/microfiber "fingers" pad to remove any of the minor debris or dirt on the surface. These use little water, so I just fill a 5 gallon pail with the water I am going to use. No damage from the low pressure, pressure washer. I carried a number of Ryobi 18 volt powered items on the boat or RV, including drill, impact wrench, oscillating cutter/detail sander, fans, lights, and a couple of 4 amp or 6 amp batteries plus a charger.

The 325 PSI pressure washer is probably even lower pressure, depending on the tip, but also works very well for getting mud off chain and anchor, as well as clearing dirt and debris from the deck near the windlass. I would not use even this low pressure on Teak decks however.

 

[Alisske]

I recently bought a “3.0mm orafice turbo tip” for my 2600psi washer. Really makes powerwashing easier and is more forgiving than the tips that come with it. Leaves no marks etc..

If you do powerwash, just be prepared to buff/wax. Almost any gelcoat can come back with a good wash/buff/compound/wax.

I think your absolutely fine as long as your not hammering the seams etc….

 

[Arc]

I have a diesel fired hot water pressure at my dock. You can’t believe the difference and I have the preassure set at 800psi.

 

[RT Firefly]

Greetings,
As mentioned, my concern with power washing is blowing out bedding compounds or forcing water into spaces it shouldn't be.

 

[Capt.Sam]

Just a few “Tips” on power washing, red = 0 degree spray pattern,has no place above the water line, Yellow is 15, Green is 25, and White is 40 degrees. For bottom cleaning use 3,000 PSI at least 4.0 GPM,Turbo nozzle will knock off poorly adhered paint, marine growth, even some invertebrates, if freshly hauled. Any 115v unit is safe all over the boat with a green or white nozzle. Just be smart, no isinglass, windshield covers or biminis. Soap from bottom up, rinse from top down, only an area big enough that the detergent won’t dry, pre-wet in direct sun or really hot days. A soft brush will is useful, clean it often to remove dirt/grit. When rinsing, overlapping strokes, hold wand at a 45 degree angle, rinse well and watch your overspray, you don’t want to get your dirt or detergent drying on your neighbor’s boat. Never Ever use a pressure washer on yourself or someone else! Happy Cleaning

 

[RT Firefly]

Greetings,
Welcome aboard.