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๐ฅ Unleash the beast: Pro power, pro mobility, pro results! ๐ช
The SIMPSON ALH4240 is a commercial-grade gas pressure washer featuring a powerful 4200 PSI, 4.0 GPM CAT triplex pump paired with a reliable Honda GX390 engine. Built on a corrosion-resistant aircraft-grade aluminum frame, it offers superior durability and portability with a 50-foot kink-resistant hose and 13" pneumatic tires. Designed for contractors and serious DIYers, it includes five quick-connect nozzles and a professional spray gun, making it ideal for heavy-duty cleaning tasks like deck restoration, graffiti removal, and equipment maintenance. Backed by multi-year warranties, this 49-state compliant machine balances power, longevity, and ease of use for demanding environments.























| ASIN | B00U77BYF6 |
| Best Sellers Rank | #21,933 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #161 in Pressure Washers |
| Brand | SIMPSON |
| Brand Name | SIMPSON |
| Color | Red |
| Customer Reviews | 4.1 out of 5 stars 522 Reviews |
| Global Trade Identification Number | 00879399001345 |
| Hose Length | 50 Inches |
| Included Components | Aluminum 4200PSI,4.0GPM,Gas GX390 |
| Item Dimensions L x W x H | 38"L x 23.5"W x 29"H |
| Item Type Name | Gas Pressure Washer, 4.0 GPM Commercial Power Washer, Cold Water, Honda GX390 Engine, 50' Hose, Aluminum Series, 49-State Compliant (ALH3228-S) |
| Item Weight | 124 Pounds |
| Manufacturer | SIMPSON |
| Manufacturer Part Number | ALH4240 |
| Manufacturer Warranty Description | Warranty Details: Engine - 3 Year Limited Commercial Warranty | Pump - 5 Year Limited Warranty | Frame - 1 Year Limited Warranty |
| Maximum Flow Rate | 4 Gallons Per Minute |
| Maximum Pressure | 4200 Pound per Square Inch |
| Model Number | ALH4240 |
| Power Source | Gasoline |
| Product Dimensions | 38"L x 23.5"W x 29"H |
| Tank Volume | 2.5 Gallons |
| UPC | 879399001345 |
| Unit Count | 1.0 Count |
| Wand Length | 31 Inches |
M**N
Great machine in terrible packaging.
Very powerful and well built machine. I am glad that I did not purchase a less powerful unit. I was disappointed with two things: 1: The shipping box does not indicate which end is up, so the delivery driver plopped it down on its side. The exhaust guard was damaged but fixable. There is very little padding inside the box, so I am sure this happens a lot. 2: the engine bolts came loose from the mounting plate during my first use. I thought it sounded a little rattle and then moved it and saw the nuts laying on the ground. Better licking hardware should come on every unit, but especially one claiming to be for commercial use. Overall, a very nice piece of equipment.
K**.
This thing is a beast!
I read a LOT of reviews here on Amazon and other online resources before deciding to make such a sizable investment in this 4200 PSI/4.0 GPM machine. This is not my first pressure washer, but my third actually. Each time I upgraded in both PSI and gallons per minute. This is my first pressure washer that is categorized as commercial use. Having finally taken the time to put this machine to the test, I can honestly say this thing has more than enough power to satisfy the average homeowner or DIYโer. As I said in the title: this thing is a beast! Mine arrived complete and undamaged. Other reviewers reported scratches and dents but that was not my experience at all. Assembly was quick and easy. My shipment contained a quart of Amsoil synthetic 10W-30 for the engine crankcase but I have seen other reviewers that got their oil in a plastic pouch. Once assembled, the crankcase filled with the supplied oil, and the fuel tank filled 1/2 way, I hooked up the garden hose and bled the air out for 30+ seconds as recommended. Set the throttle to half-way and closed the choke and gave the starter a quick pull and it fired right up on the first attempt. After allowing the engine to run at partial throttle with the trigger open to keep the water flowing and the pump cooled for a few minutes, I increased the engine speed to approximately 3/4 and started cleaning the concrete patio as my first project with this unit. The pressure even at less than wide open on the Honda GX390 was more than enough to get the accumulated grime blasted off effortlessly. Next up, I connected my 15โ surface cleaner which really sped up the process. The 4240 pressure and water flow are a perfect match for the Karcher 15โ surface cleaner. With all of the positive attributes of this machine, there is one thing that I feel is a negative: the hose. Itโs more than long enough for most jobs but the stiffness makes moving around with it a real challenge. Given the higher than average PSI capabilities of the ALH-4240 itโs not surprising that the pressure hose is more on the stiff side, but as others have commented, it would be a good idea to upgrade to a better hose. Honestly, at this price point, a better quality hose should come with it. Overall, the ALH-4240 is a great pressure washer that has all of the power that the average person could want for DIY use. The high PSI and GPM make short work out of even the toughest cleaning projects. Time will tell if it lives up to the Simpson advertised claims of dependability and reliability.
S**S
Quality assurance issues and excessive vibration transfer to the end user in included hose.
This review is for the Simpson ALH4240 4200 PSI pressure washer. I replaced a similarly powered washer with this unit. The unit arrived with no apparent shipping damage and all appeared new. The โissuesโ, starting with least severe first. 1. The nut nearest one of the tires, threading through a bolt to the engine platform was not adequately tightened, and the nut fell off during the first usage session. Luckily I noticed it on the ground. 2. The aluminum handle bar (near the โdashboardโ) had several burrs and nicks, which need to be buffed down to avoid scratches / cuts / etc while moving the unit. 3. It seems the included hose is unsuitable, and Simpson should provide a suitable replacement. Itโs extremely rigid due to the metal layer running the length of the hose. The biggest issue with this is a very large amount of mechanical vibration is transferred from the motor/pump directly to the end-user/operator. ITโS PAINFUL TO EVEN USE THIS FOR MORE THAN A FEW MINUTES. Repetitive stress injury in the wrist/arm seems a real potential, on top of reduced productivity. The amount of vibration is obvious if you put your foot lightly on the hose. โFightingโ the hose while moving around is an issue too. You need to test this and have a mechanical engineer address the issue.
J**N
Impressive Pressure Washer
This is an impressive machine. I bought the model with the Honda motor and CAT pump, this will clean just about anything! I bought it as an upgrade to an electric pressure washer, and this is a major upgrade! More power than I need for most jobs around the house, but it's good to have it if needed. My next project will be removing polysand from the joints of 960 sq.ft. of patio pavers. This thing will get a workout! My only feedback for improvement is the quick start guide did not flow from one page to the next correctly. It has several languages within and you have to search though the entire thing for your next steps, flipping it upside down or even going backwards to find the next steps. At least they were numbered, but I feel as though theu could do much better. Other than that, this pressure washer will not disappoint! Great product!
T**.
Amazing power washer, I'm very happy and it was well worth the price!
This is a solid unit, very happy with this purchase. Well worth the price. I had a different brand which was an electric model previously but it was only good for small projects. This Simpson 4200 PSI gas pressure washer is a game changer and it has cut my cleaning time down by more than half. It's also easy to use and start. I highly recommend it to anyone looking for something more commercial-grade and more powerful than just a high-end consumer power washer. This power washer is amazing.
T**M
Great Product - Packaging & Handling, Not So Much
This Simpson pressure washer is top quality. The Honda GX390 engine coupled with the CAT pump can handle any job to include a 20" surface cleaner. My only reason for the 3 star review is the packaging and delivery. It boggles my mind that Amazon would actually package an expensive, heavy, bulky item with no support other than a cardboard box. Further, the unit was left on my porch actually upside down. Beware! ... this item clearly states "Non Returnable" so thank goodness it wasn't damaged.
K**S
Awesome pressure washer
Works great and a lot of power. Can't beat the Honda and Cat combo. Quick to put together and it arrived in great shape.
A**R
Great pressure washer
Of course the Honda engine is very well built as is the aluminum frame. All Honda motors have a weird oil level check they should throw away the dipstick you just fill the oil to the bottom of the threads it's less confusing. Strong CAT pump wish I had a better place to coil the hose as it's super stiff but obviously well built
B**H
๐ค
Trustpilot
2 days ago
5 days ago