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SIMPSON

Simpson Cleaning 4200 PSI Gas Pressure Washer, 4.0 GPM Power Washer for Commercial Use, Honda GX390 Engine, 50-Foot Steel-Braided Hose, Aluminum Series, 49-State (ALH4240)

  • Based on 1,498 reviews
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Availability: Only 6 left in stock, order soon!
Fulfilled by MaxTool
Arrives Jul 11 – Jul 12
Order within 11 hours and 43 minutes
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Style: 4200 PSI Honda GX390


Features

  • Professional Performance: Easy-to-assemble and easy-to-start with its HONDA GX390 engine commercial series engine, the Aluminum Series power washer is great for contractors who specialize in deck cleaning, wood restoration, and all professional services
  • Power and Durability: A powerful, reliable, maintenance-free CAT Industrial triplex plunger pump delivers 4200 PSI at 4.0 GPM and includes thermal relief to prevent overheating
  • Sturdy and Portable: The aircraft grade aluminum platform with brushed extruded aluminum tubing offers durability and corrosion resistance; 13-inch premium pneumatic tires deliver ease of maneuverability across various terrain and uneven ground
  • Includes Quality Simpson Accessories: Monster 3/8-inch x 50-foot high-pressure hose is kink- and abrasion-resistant; 5 Quick connect nozzle tips: 0, 15, 25, 40 and Soap; 16-inch steel wand/lance; Professional spray gun with safety lock-out
  • Important Notes: 49-State Compliant; Pump/Hose Connection: Threaded M22 connection

Description

The SIMPSON Aluminum Series pressure washer 4200 PSI at 4. 0 GPM is great for construction, equipment upkeep, and facility and fleet maintenance cleaning. With a powerful HONDA GX390 engine, reliable CAT triplex pump, and ultra lightweight aircraft grade aluminum frame, this pressure washer is the optimum blend of maneuverability and performance. The ALH4240 also comes with a 50’ hose, ergonomic spray gun, and 5 Quick Connect nozzles. Designed to meet the rigorous demands of the cleaning professional, the SIMPSON Aluminum Series frame is crafted of 100% aircraft grade aluminum, making it lighter in weight than most steel frame pressure washer designs. Perfect for contractors who specialize in deck cleaning, wood restoration, paint preparation, graffiti removal and all other professional cleaning services. The SIMPSON Aluminum Series designed for optimum performance in the harshest environments. 10 Year Limited Frame Warranty, 5 Year Limited Pump Warranty, 3 Year Limited Engine Warranty. Includes: Pressure Washer, Hose, Gun, Wand, 5 Quick connect nozzle tips, Detergent siphon tube with filter, Engine Oil, Quick start set up guide, Owner's manual.

Brand: Simpson Cleaning


Power Source: Gasoline


Color: Red


Maximum Pressure: 4200 Pound per Square Inch


Item Weight: 124 Pounds


Hose Length: 50 Inches


Product Dimensions: 38"L x 23.5"W x 29"H


Tank Volume: 2.5 Gallons


Maximum Flow Rate: 4 Gallons Per Minute


Global Trade Identification Number: 45


Brand: Simpson Cleaning


Power Source: Gasoline


Color: Red


Maximum Pressure: 4200 Pound per Square Inch


Item Weight: 124 Pounds


Hose Length: 50 Inches


Product Dimensions: 38"L x 23.5"W x 29"H


Tank Volume: 2.5 Gallons


Maximum Flow Rate: 4 Gallons Per Minute


Global Trade Identification Number: 45


UPC: 879399001345


Item Weight: 124 pounds


Manufacturer: SIMPSON


Item model number: ALH4240


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jul 11 – Jul 12

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • This thing is a beast!
Style: 4200 PSI Honda GX390
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 DIY’er. 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 15” surface cleaner which really sped up the process. The 4240 pressure and water flow are a perfect match for the Karcher 15” surface cleaner. With all of the positive attributes of this machine, there is one thing that I feel is a negative: the hose. It’s 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 it’s 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. ... show more
Reviewed in the United States on September 17, 2024 by Kenneth B.
    • Strong and reliable (detailed review over the year)
Style: 3400 PSI Honda GX200
Wanted to wait for some time to pass before making a real a review on my pressure washer. Purchased in sep 2021 and it’s now Jan 2025, so I have used it for 3 warm seasons since I only use it during the warmer months in PA. Did A LOT of researching before pulling the trigger on getting this unit. Some might think it’s expensive for someone who may only use it for home use and not commercial, but it’s perfect and reliable! I wanted something that would be versatile and beneficial with all projects. I always do the recommended maintenance and when storing for winter I winterize it. Maintenance is key for anything and I believe taking care of this will make it last for years of use. Main selling points for me and things I like: - CAT AAA pump, Honda engine, warranty, GPM, heavy duty but “light weight” frame/wheels, and being able to not worry about damaging the pressure washer if you release the handle while it’s running (not something I do often but know that’s a big no no when it comes to other pressure washers that don’t have the feature to allow this. High PSI and also the ability to lower the rpm’s to use it for lighter duty tasks. My complaints over the years: - The rubber feet that come with this unit are garbage, plan on replacing them with bigger and better feet because these ones will not last and the pressure washer will walk around on you. - I wish there was a better design for changing the oil, it’s a pain in the butt but with the right set up it wouldn’t be a big deal - It a little awkward when wheeling it around but it’s not a big deal and is only heavy if you are picking it up by yourself to go up stairs or things like that. Overall I would highly recommend this and would purchase again! Hope this helps you :) ... show more
Reviewed in the United States on February 2, 2025 by Tim
    • would not run :(
Style: 3600 PSI Honda GX200
Purchased this machine because it had the Honda GX engine & because it was made in the USA! Have several other Honda powered pieces of equipment that have been reliable, easy start and trouble free. However, this SIMPSON power washer would not start I should say, after about 5 tries it did start several times but then immediately died Took me repeated tries (nearly an hour) with waiting, in case it was flooded, between tries. Once I did finally get it started I could not adjust the choke or throttle, as suggested in the manual, without the machine dying . The machine only ran for a few minutes before it began backfiring. It would only run without backfiring if the water wand was kept in the washing position at all times. I could not take my hand off the wand handle or the machine would backfire. After calling the help line their only suggestion was for me to take this brand new machine into the repair shop. It was Saturday, mid day by this time, and the repair shop did not have a repair person available to help so would have to leave it for them to look at in a few days or so. Out of frustration I tried to go ahead and continue using it and kept the power wand in the open-wash position but gradually the machine started backfiring anyway. I turned it off and let it rest thinking maybe it was hot (my previous power washer - 15 years old - would run and run until out of gas, then I would let it rest and cool before re-filling the gas tank.) After turning it off, I was not able to restart it again. I had hired a couple young men to come help me move items, power wash under & behind, then return the items to their proper place. Many of the things had already been moved. I Needed to get power washing under and behind before returning them to their place. I had already been paying for them to stand around while trying to get the machine started then trouble shoot on the phone. I had to go buy a Costco power washer so I could get the work done while I had helpers!!! Now the company whom sent this is saying it can not be shipped after oil & gas have been added. It had oil in the pump when it was shipped so this does not ring true. Besides I can completely empty the gas and let any residual evaporate and the oil can be drained. I do not need 2 power washers and certainly not one that doesn't work! Needless to say I am not a happy camper right now! I purchased this through AMAZON so hopefully their guarantee will help me with this problem. P.S. This machine is now on line for $100.00 less than my purchase price :( ... show more
Reviewed in the United States on August 21, 2019 by Valerie G.

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