Pressure washer - max/min

Rich Stidger · Aug 31, 2019

Brian - There is lots of discussion on the use of pressure washers here. Some say to never use them because of potential damage to the surface. Others say use a low pressure - maybe 1600psi? - and hold the wand 12" or more with a relative wide pattern. I know it is hard to quantify what I just posted.

Personally I have used my Home Depot Husky electric 1800 psi unit on my decks. I did use a wide pattern - maybe 5-6" on the deck and held off maybe 12". It was quite a while ago and I only used it once. It is an effort to lug the washer up onto the deck when on the hard. I was trying to get rid of the embedded grunge in the none skid areas, and it did work well. I'm not convinced it was worth the effort, hence I have not repeated.

What does work for me on the non-skid is to spray a bleach mix with car wash soap on the deck and after a few minutes scrub with a medium stiff bristle brush. Rinse off very well with a hose. You can also use Soft Scrub with bleach. BE SURE TO WEAR OLD CLOTHES AND SHOES WITH THESE BLEACH PRODUCTS!! And change your clothes afterwards so you don't transfer the bleach solutions to unintended areas.

MikeHoncho · Aug 31, 2019

I have a small electric model I keep on the boat and I think is is around 2 gallons per min. I use it 2-3 times a year to knock off the build up. I don't use it for routine cleaning. Screwing up sealants is a legitimate concern. Psi isn't as critical as gpm in my opinion. I have a 4600psi, 6gpm, 13hp PW at home that is a ass kicker and gets the job done.

This is the one I bought for the boat.

Screenshot_20190831-093832_Amazon Shopping.jpg

Don S/V ILLusion · Aug 31, 2019

Regardless of what pressure rating you decide to use, be careful around any teak (or any wood). Even a low pressure can eat it up. That’s not to say don’t ever use it on wood - I used to clean our wood deck all the time with low pressure to no harm with careful use

The Shadow Knows · Aug 31, 2019

Brian,

unless you want to blast or take away paint, I suggest an electric pressure washer.
I use mine for deck & sails using different pressure settings & spray nozzle adjustments.
I use this for my boat, for washing my vinyl siding, concrete walkways & even for washing my car.
Different supply water pressures & hose sizes makes a difference in flow & pressure.

There are many brands out there, but I have my Husky 2000PSI. It does what I want.

BigEasy · Aug 31, 2019

Brian,
I purchased a pressure washer approximately 20 years ago; it is undoubtedly one of the most versatile tools that I have purchased. I have a 2500psi, 3GPM, 6 HP Honda engine, and CAT pump. I use a 0 degree nozzle mostly and no detergents nor solvents; just pressurized water to clean the boats, soffit/fascia on the house, truck, patio/sidewalks/driveway, dock box, and deck. The amazing thing about it is that I never drain the gas (non ethanol only), change oil rarely, was flooded in Katrina, and it still starts always on the second crank! I would definitely choose one with a Honda engine and CAT pump. I would avoid an industrial washer with high psi ratings because of the potential damage that can be inflicted to structures that you are cleaning and you personally. I know of one individual who was lacerated severely on the foot and required surgery because of water and air injection into the soft tissue from a high pressure washer. I purchased a small electric washer a couple years ago as recommended by my dock neighbor because I could keep it in the dock box for convenience. It was a total waste of money; too small of pressure foot print to clean the deck thoroughly and efficiently. I have two ramps that I use to load and unload the gas pressure washer, when I use it on the boat. As Rich mentioned, you have to use common sense when using it on the boat, keep the nozzle about 12" away from the deck and don't apply pressure directly to window seals, hull/deck joint, and bedded fixtures such as chain plates. I can thoroughly clean mildew stains, bird and spider droppings in 30 minutes, more effectively than any other method that I have tried over the years. I have not seen any detrimental effects on two boats over many years. Yes, it is an inconvenience to haul the washer to the boat; however, it beats scrubbing the deck for two hours with a deck brush and still not achieving as good a result as the washer. Make sure that you purchase a grey or white accessory hose so it doesn't cause black marks on the deck when dragging the hose on the deck. If I were to replace my present washer, I would purchase a Simpson model 60735 washer; it has all of the specs that I mentioned, as well as an aluminum frame. You will not be disappointed and it should last a lifetime!

SycloneDriver · Aug 31, 2019

I have a 20 year old Karacher M520, or something like that, that I keep at the boat. If I remember correctly it's about 1600 psi @ 1.6 gpm. I also have an AR Blue Clean 630 SS Hot. The AR is 1500 - 1600 psi @ 2.1 gpm. The AR is a great unit but it's heavy and too expensive to leave in the dock box. I almost forgot about my gas powered unit that I haven't stared in years. I have used several others too.

I really prefer electric unless I need lots of power. Gas units make lots of noise and the exhaust stinks, you won't make any friends at the dock with one.

I agree with the others that place a priority on GPM over PSI. I have used several cheap low GPM units and think they are a complete waste of time and money. Look for a unit that has at least 1.5 GPM.

Bleach and boat soap in a bucket of water and a brush also does a good job.

Ken Cross · Aug 31, 2019

Cheap ($79) Harbor Freight electric (1,200 psi). I keep the big gas job at home. The litte electric is slow, but that's fine. I still avoid areas where sealant could be damaged.

Ken

CarlN · Aug 31, 2019

Think about storage. I got this little one that just gets tossed in a locker. And for $62! (“Original” version) It’s not nearly as strong as the gas driven ones used by the boatyard but plenty for decks and topside cleaning. Obviously, much stronger than a hose and spray gun. It uses just over 1 gpm so it runs off the boat’s fresh water pump. The warranty appears good too. https://www.amazon.com/gp/product/B07G35BRLT/ref=ox_sc_saved_title_3?smid=ATVPDKIKX0DER&psc=1

dlochner · Aug 31, 2019

We have a small Greenworks (from Lowe's) pressure washer. Not sure of the rating, it was the cheap one, around a hundred bucks as I recall.

As others have mentioned, be careful around teak and fittings. The pressure can erode the wood and blast out the sealant around fittings. It is good at cleaning nonskid.

Tally Ho · Aug 31, 2019

Brian D said:
I want to get a pressure washer. Of the things I will use it on, one is the boat. But I don't want to get something that will not do a good job, and conversely, I don't want to strip the gel coat off.

So with that in mind, what would be the maximum and minimum PSI I should be looking at? And what angle nozzle? I know some of you guys have pressure washers so will be speaking from experience. Probably more trailer sailors than big boat guys.

Thanks in advance

You don’t mention what else you want the PW for... I have a gas engine driven PW, 3,000 PSI. I mostly use it for chores around the house.

I have a multi-head nozzle...I can switch quickly and without tools.

Amazon.com: M MINGLE Pressure Washer Nozzle Tips, 6 in 1 Changeover, 1/4 Inch Quick Connect, 4000 PSI: Gateway

www.amazon.com

For me, the higher the PSI, the better. And I can use the adjustable tip to make the pressure less damaging.

I have almost written my name in my deck boards trying to clean them...so you do have to be careful.

I have used mine on my boat before, but I am careful to stay away from teak, caulking, etc.

If I ONLY was going to use it on the boat an electric one may be OK. But for me, higher PSI gas driven pump works better.

Greg

Meriachee · Aug 31, 2019

Worx Hydroshot 20v cordless, breaks down nicely enough to fit into the lazarette. It looked like a bit of a toy, but it's proven itself on the boat

Ken Cross · Sep 1, 2019

Brian D said:
Thanks for you input and advice guys. Funny that I should have done a search first but for some reason I didn't. Don't even follow my own advice.

So GPM is the key, not PSI? That is interesting I figured that PSI does the work, not GPM. I would see that GPM keeps the water flowing and if you have a low (<1.5) GPM you will not get the PSI. Whoa. Too much to think about.

I will look around. I don't want to spend a large sum of money on a tool that I will hardly use, but still need one. This is why I asked. I see the Portland Pressure Washer from HF and it is reasonable price wise. 1.3 GPM and max 1750 PSI. But there are a few that are just around the same price with higher GPM.

Thanks again

It's actually both pressure and volume. To get an accurate measure to compare them muliply pressure by volume.

Ken

rgranger · Sep 2, 2019

I have a big gas one I keep at home but I’ll second (or third and forth) a small electric for the boat. That are small and easy to move around

jviss · Sep 2, 2019

Don S/V ILLusion said:
Regardless of what pressure rating you decide to use, be careful around any teak (or any wood). Even a low pressure can eat it up. That’s not to say don’t ever use it on wood - I used to clean our wood deck all the time with low pressure to no harm with careful use

When I was looking at boats three years ago I caem across a Tartan 3700 that I really liked, except that the owner had "cleaned" the teak with a pressure washer, absolutely destroying it; the pulp pf the wood was all pulled out. The only solution was to replace all of that wood, at great expense.

I wouldn't use a pressure washer on a boat. It's like a "use a bigger hammer" solution. If water, soaps, solvents, or careful, controlled controlled abrasion don't address the issue, higher water pressure likely won't without accompanying damage.

bawlmer · Sep 2, 2019

I got a cheap Harbor Freight electric that I have had for 4 years now. I use it exactly once a year for Spring commissioning. I am very careful when around any joined surfaces. I try to use minimum force. I believe the benefit of a once a year use outweighs any potential risks to the gelcoat.

Ken Cross · Sep 2, 2019

bawlmer said:
I got a cheap Harbor Freight electric that I have had for 4 years now. I use it exactly once a year for Spring commissioning. I am very careful when around any joined surfaces. I try to use minimum force. I believe the benefit of a once a year use outweighs any potential risks to the gelcoat.

We get some black spots that I have found no other way to remove and the runoff doesn't ruin the wax on the sides of the hull.

Ken

SycloneDriver · Sep 2, 2019

I've been using pressure washers on boats for over 10 years and I have never knowingly damage the gelcoat. I avoid using them on: wood, gaskets, sealant, sails, my feet, you get the idea.

A high PSI / low GPM machine is like trying to clean with a stiff toothbrush and softscrub, it does a good job but takes forever to clean the entire boat. You need a machine with enough GPM or the work area is too small and the job takes too long.