Simpson ALH4240 - 4200 PSI 4 GPM Gas Pressure Washer With Honda Engine
The Simpson Aluminum ALH4240 is a gas-powered pressure washer offering a maximum water pressure of 4200 PSI and flow of 4 GPM. (Read full specs)
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Description
The SIMPSON ALH4240 is designed to meet the rigorous demands of the cleaning pro. Heavy-duty pressure washers with flow and reliability. Perfect for contractors who specialize in deck cleaning, wood restoration, paint preparation, graffiti removal, and all other professional cleaning services.
Zoom on the Simpson ALH4240
The Simpson ALH4240 is a commercial pressure washer, that provides its users with an all-around versatile cleaning experience, and enables:
- targeted spot cleaning for hard, unpainted surfaces, reaching elevated areas, and thoroughly removing stubborn stains
- complete cleaning of hard surfaces, vehicle washing, and surface prep for painting
- delicate surface cleaning, andbroad area cleaning with reduced pressure
- applying detergent and cleaning solutions, and rinsing surfaces
Its power characteristics and design, its main features and all its additional features are presented ahead.
Power
The Simpson ALH4240
With a powerful 389cc (11.7 hp) engine, its triplex pump delivers a pressure of 4200 PSI (roughly 70 times more than a standard garden hose) and a flow of up to 4 GPM (CETA-certified values), resulting in the Simpson ALH4240's cleaning power of 16800 Cleaning Units.
The Honda GX390 engine of this gas-powered pressure washer is initiated by a classic pull-start mechanism.
Fuel for the pressure washer is housed in a steel tank capable of holding up to 1.6 gallon of gasoline.
Design & Handling
Characterized by its wheelbarrow layout, the Simpson ALH4240 provides improved mobility and stability, facilitating easy movement and steadfast operation for effective cleaning results. Built with an aluminum frame, this pressure washer prioritizes mobility and longevity, offering corrosion resistance and lightweight design for ease of use and durability. The handle adds to the ALH4240 convenience of transport.
Weighing in at 133 lbs, it's safe to say this unit isn't lightweight, which might pose difficulties for users when it comes to lifting and transporting, particularly over uneven surfaces. A key role in its final weight is played by its 389cc Honda GX390 engine, the triplex pump and aluminum frame. Despite this, the presence of two 13" pneumatic wheels reduces the complexity of moving the ALH4240, even on rugged surfaces.
Main Features
The Simpson ALH4240
The Simpson ALH4240's package includes a spray gun, a wand, a pressure hose, 5 nozzles and a detergent injection feature, with a more detailed description below.
- Soap injection: Even though the device doesn't have a soap tank, detergent is supplied by a siphon hose. Attachment of a soap nozzle prompts the pressure washer to automatically introduce and blend the detergent with the water.
- Pressure hose: With a set of convenient hooks, the unit offers a practical solution for maintaining workspace order, allowing the included 50 ft ⌀3/8" high-pressure hose to be neatly stored when idle.
- Spray gun and wand: The included classic ergonomic spray gun and its steel wand can be easily stored in a side hook.
- Nozzles: The table below shows you the 5 included nozzles and the surfaces they're the most appropriate for.
0° | 15° | 25° | 40° | Soap | |
|---|---|---|---|---|---|
| Concrete, brick, masonry | |||||
| Siding, gutters, house | |||||
| Fencing, deck, patio | |||||
| Lawn equipment, boat, RV |
Please note: The shapes of the nozzles depicted above are for illustration purposes and may vary. Symbols used include a for 'Not recommended,' a for 'Suitable,' and an for 'Use with caution.'
Other Features
Some of the included accessories
- Dial-N-Wash®: Simpson’s Dial-N-Wash® is an adjustable pressure regulator that allows you to choose a desired pressure for your specific cleaning application. High, medium and low pressure settings can be switched between easily by a simple twist. Its design assures its compatibility with most pressure washer standard spray wands and standard guns with threaded fittings.
- Onboard storage: The Simpson ALH4240 features a handy storage area, which allows you to neatly store nozzles and accessories and be always prepared by having everything needed at hand.
- Safety: Safety of operation is enhanced by a low oil protection, a trigger lock mechanism (which prevents accidental operation) and a thermal relief valve (which helps to prevent internal pump damage).
- Accessories: The Simpson ALH4240 comes with an owner's manual (opens in a new tab) and some basic documentation to get you quickly started. On top of that, you also get soap hose, oil, pressure regulator, spray gun, pressure hose and wand.
Product Videos
The Simpson ALH4240's performance versus other pressure washers
The following charts are provided to give you an idea of how the key specs of the Simpson ALH4240 compare to similarly priced pressure washers.
- Equipped to deliver up to 4200 PSI, the Simpson ALH4240 is recognized as one of the gas-powered models delivering higher-than-average water pressure, priced between $1100 and $1500. Prioritizing the highest water stream power? Check out the DeWalt DXPW4440—a top contender in this price range, delivering up to 4400 PSI.
- The water flow of this washer, which reaches up to 4 GPM (gallons per minute) is one of the highest values found in the above-mentioned price range.
- Featuring 16800 Cleaning Units (PSI X GPM) in total, the ALH4240 ranks among the more efficient options in its respective price bracket. If the highest overall cleaning power is a priority, the DeWalt DXPW4440 and its 17600 Cleaning Units are notable for their higher potential cleaning efficiency compared to units in the same price range.
Price comparison
As you can see from these interactive charts, when compared to other gas-powered washers between 16500 and 17000 Cleaning Units, the Simpson ALH4240 is on the average side of the price range.
Therefore, this pressure washer nicely fits in the expected budget for this kind of cleaning power.
The bottom line
- In the expected price range
- 10 year (limited) warranty
- Triplex pump
- Honda engine
- Designed to be stable
- Aluminum frame
- Good range of nozzles included
- Onboard storage
- Several security features
- High PSI for the price
- High GPM for the price
- High CU for the price
- No soap tank
Do you own the Simpson ALH4240 and agree (or disagree) with these strengths and weaknesses?
Let us know and write your own review.
Features and Specifications
| Fuel | Gas-Powered |
|---|---|
| Engine | 389cc 11.7 HP Honda GX390 OHV 4-stroke |
| Pump | CAT Triplex |
| Water | Cold (100°F max.) |
| PSI | 4200 |
| GPM | 4 |
| Cleaning Units | 16800 |
| Pressure control | Dial-N-Wash® + unloader valve |
| Frame | Aluminum |
|---|---|
| Handling | Wheelbarrow |
| Wheels | 2 wheels, ⌀13", pneumatic |
| Weight | 133 lbs |
| Dimensions | Approx. 38 x 23.5 x 26 in (L x W x H) |
| Hose storage | Hooks |
| Soap injection | Via siphon hose |
|---|---|
| Nozzles | 0°, 15°, 25°, 40°, Soap |
| Quick connect nozzles | Yes |
| Onboard storage | Yes |
| Hose | 50 ft, ⌀3/8 |
| Security | Low oil, trigger lock and thermal relief valve |
|---|---|
| Emissions | EPA |
| Included accessories | Oil, steel wand, spray gun, high pressure hose, soap hose, 5 nozzles, Dial-N-Wash® pressure regulator |
| Warranty | 10 years |
| Series | Aluminum |
| Other model numbers | 60688 |
| UPC | 879399001345 |
We've taken extra care to research and verify each of the specifications above. That said, occasional mistakes or omissions are still possible. If you spot any missing or inaccurate information, feel free to suggest a correction so we can address it.
About Simpson
Simpson has over 50 years of experience making quality products for the outdoor power equipment industry. Part of the FNA Group based in Pleasant Prairie, Wisconsin since 2006, they are a vertically-integrated company, meaning most of the parts and accessories are manufactured and assembled by them. Their manufacturing facilities are international, but their gas-powered pressure washers are made in the USA. With the company motto "Driven by Performance", Simpson continues to offer a great variety of pressure-washing systems for the homeowner or the professional contractor.
Warranty Information
The Simpson ALH4240 is covered under a warranty for up to 10 years. This warranty may be limited and may not cover all parts of the unit.
For more information about the warranty of Simpson pressure washers, please contact the Simpson Customer Support: 1-877-362-4271.
