Am looking at possibly purchasing a gas pressure washer but it's not so simple. I am looking for one that will gravity feed and most say they need a minimum inlet pressure that can't be reached by gravity unless you buy an expensive belt driven washer. People have hooked them up to a tank but usually you can't get the full pressure they put out so it's a waste. Went to the 1st place that all they do is pressure washers and steam units and 3 times the guy gets a call from head office or his boss and says I have to take this call. Shouldn't the customer standing in front of you come first? Then he says all the washers need to hook up to a pressurized garden hose or you need a booster pump coming off the tank. Then I show him their pamphlet that shows a pick up skid unit with a tank and the P washer I was looking at. He thinks it uses a gear driven pump but finds a pic. on their website that clearly shows no gear drive but a very short thick wall rubber suction hose about 18" long. Nothing like knowing the products you sell. 2700 PSI and 3GPM, $945 with Kohler engine and $100 extra for Honda GX engine. Didn't recommend Honda clone engine for $795. Was overall helpful and says his manager may have a demo unit he could sell at a discount and may be interested in sponsoring my track. Gave me his managers card. Not too bad other than taking 3 phone calls in the middle of our conversation. Go to the next place that's supposed to specialize in P washers and the guy didn't know much other than they should have a pressurized water supply. They had some 24 volt RV type pumps for sale on the counter 3.6 GPM and 45 PSI. I asked him about using a pony pump (12 volt or 115 volt) and he says it wouldn't have enough pressure to do much cleaning??? To feed the p washer you idiot not to try and clean with. Just clueless. I lost all faith in him after that. Went to the Hotsy place and their prices were crazy high. $1950 for a 2000 PSI 2.9GPM pressure washer. Another place that specializes in pressure washers wanted $2150 for 2000 PSI 3 GPM washer with a Cat pump and idle control. I think I'm better off with a commercial unit than a residential unit but maybe someone on here uses a pressure washer with a gravity feed tank? Maybe a box store washer is good enough?
Call a "mobile" pressure washing place or "drop by".. They ride around town w/ a giant water tank on a trailer or in the back of their truck..
I've used a 110 pump that cost around $139 with a 275 gallon tank and a 3000 watt generator running pump and washer. Not a very powerful washer but the pump was more than enough. Hope this helps. Also, adding hieght to the tank adds pressure to the feed.
I have used several of them out of a barrel laying on it's side many times. My brother is a commercial crabber and uses the cheapest one he can find on his boat, and he is picking up water from about 3 feet below the pump. I think they are full of it.
I have one of these with not only the triplex pump, but the heater too. And, no "feed" pump. And, the triplex pump is at the 1/3 mark up the tank. And my triplex pressure washer from 30 years ago looks like the same pump as on my Northstar unit, and I'll gravity feed it all day long.
We have an ez clean 4000 hot washer and it will Not feed for whatever reason from a 275 tote tank even with the tank on a flatbed truck and washer on the ground a little garden hose pump fixes that it needs power for the heater anyways
Have a 1050 cat 15gpm 2000 psi Also a 3675 cat 30gpm 1800 psi Both suckling 140 degree water out barrels standing beside the pumps built them myself . Dont believe one word they tell you ,just make sure your suppy is 3 times the size of the discharge
If you are looking at 25oo psi and 3 gpm, you should be able to get a cheap 12v pump to feed the water. I am assuming that if you are gravity feeding, you will have a water tank on some type of vehicle which could provide the 12v. That may be a poor assumption on my part.
Pressure pumps are expensive. If you don't supply enough head, the pump will cavitate. The pumps that run at engine speed are the most sensitive, The belt drives slow the pistons so they aren't as sensitive to cavitation. Takes a while, but the cavitation eventually kills the pump... if something else doesn't get it before. ( Like dirty water)
Yes to belt drive pumps for gravity feed but they are expensive. Talked to Easy kleen. They were the 1st ones I talked to that had a pick up skid with tank and pump with short hose. They have the same set up as a trailer unit with a larger tank too. It seems like the best deal for a more commercial pump than a box store residential washer. They recommended putting a bigger filter on the feed line than just the little strainer it comes with. I think having something that will last and is repairable is better than having a residential unit. I'll see if they have a demo unit or possibly want to sponsor my track.
I did commercial pressure washing for about a year we ran belt drive cat pumps they would do 4000 psi and 5.5-6 gpm min all day long and would suck the tank dry sitting about a foot above the bottom of the tank our units ran 18hp v twin Honda’s with 110 volt diesel fired heaters and 2500 watt generator head would also suck the seals out of a faucet if hooked direct to one without enough flow
A heads-up. An incident with a NorthStar pressure washer where the heating coil (weighs about 60 pounds) ruptured and the force dumped it maybe 30 feet away. Fortunately the guys using the pressure washer were up on top of the boom in the left of the photo so it went nowhere near them, the bang made them crap themselves though. Could have been a different story if someone had been standing in the path of the heating coil as it was launched into orbit.
Not to mention the boiling water spewing everywhere.
Apparently it flew almost as high as it travelled horizontally. I think if you were unlucky enough to get hit by a 60lb coil flying at twice the speed of sound the boiling water would be the least of your worries. YMMV.
I used to work on hydrovac and steam trucks. Most of the trucks ran a Triplex or Cat high pressure pump. They were all gravity feed. Never had any issues. This was a decade ago though so I'm foggy on the model numbers and such.
I gravity feed my big hot washer from a 275 gallon tank in an enclosed trailer from a 10' section of 1" hose. 4000 psi 4gpm and wheel the washer outside of the trailer so that there is at least 12"+ of differential pressure and the pump never cavitates. The size of the feed hose is what will matter in this application. Larger is always better and keep the tank elevated - you should not have problems. I've also recently built a pto hydraulic powered pressure washer in my service truck. It's fed off a 50 gallon barrel. 4 gpm, 4ksi. No problems with cavitation, yet. Again, short feed hose, non-collapsible, water level kept above pump intake and there is no problems at all. And if I burn up a $300 pump doing this, not a big deal for my business as for what it adds to my uptime.