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)
Features and Specifications
|Water||Cold (100°F max.)|
|Engine||389cc 11.7 HP Honda GX390 OHV 4-stroke|
|Other model numbers||60688|
|Soap injection||Via siphon hose|
|Nozzles||0°, 15°, 25°, 40°, Soap|
|Quick connect nozzles||Yes|
|Hose||50 ft, ⌀3/8|
(L x W x H)
|Approx. 38 x 23.5 x 26 in|
|Pressure control||Dial-N-Wash® + unloader valve|
|Wheels||2 wheels, ⌀13", pneumatic|
|Included accessories||Oil, steel wand, spray gun, high pressure hose, soap hose, 5 nozzles, Dial-N-Wash® pressure regulator|
|Security||Low oil, trigger lock and thermal relief valve|
Unlike many websites, we did our best to research each of the specs above. That being said, we are not immune to making the occasional mistake or omission. Should you notice any missing or incorrect values, don't hesitate to suggest improvements so we can address the issue.
Zoom on the Simpson ALH4240
The Simpson ALH4240, a heavy duty, commercial pressure washer, gives its user an all-around versatile cleaning experience, topped off by the following features:
- spot cleaning of hard, paintless surfaces and reaching far-away areas
- thorough cleaning of hard, paint-free surfaces
- cleaning of painted or delicate surfaces
- application of detergent and cleaning solutions
Its power characteristics and design, its main features and all its additional features are presented ahead.
Using a powerful 389 cc (11.7 hp) engine, its triplex pump delivers a pressure of up to 4200 PSI (roughly 70 times more than a standard garden hose) and a flow of up to 4 GPM (CETA-certified values). Together, the values result in a cleaning power of 16800 Cleaning Units.
The Honda GX390 engine of this gas-powered pressure washer gets started by a classic pull-start mechanism.
Gasoline storage is facilitated by a steel fuel tank with a maximum capacity of 1.6 gallon.
Design & Handling
The wheelbarrow design of the Simpson ALH4240 grants mobility and stability to the unit. The aluminum frame grants the device a good durability, as it will not rust. The handle adds to the ALH4240 convenience of transport.
This model weighs 133 lbs. For this reason, it cannot be called lightweight and thus, carrying and transporting it might be somewhat challenging. Its 389 cc Honda GX390 engine, the triplex pump and aluminum frame add up to a large chunk of the device's weight. However, the unit’s two 13" pneumatic wheels are crucial to its maneuverability, since they provide a smooth method of manipulation on the job.
The Simpson ALH4240 comes with a spray gun, a wand, a pressure hose, 5 nozzles and a detergent injection feature, which are detailed below.
- Soap injection: While the device doesn't feature a soap tank, detergent supply is ensured by a siphon hose. The detergent will be added automatically to the water when a soap nozzle is attached.
- Pressure hose: A neat storage for the included 50 ft ⌀3/8" high-pressure hose is facilitated by a set of convenient hooks.
- Spray gun and wand: A side hook allows for an easy storage of the included classic ergonomic spray gun and its steel wand.
- Nozzles: The 5 nozzles included with the device, and the respective surfaces which they’re the most suitable for, are shown in the following table.
|Concrete, brick, masonry||Use with caution||Suitable||Suitable||Suitable||Suitable|
|Siding, gutters, house||Not recommended||Use with caution||Use with caution||Suitable||Suitable|
|Fencing, deck, patio||Not recommended||Use with caution||Use with caution||Suitable||Suitable|
|Lawn equipment, boat, RV||Not recommended||Use with caution||Use with caution||Use with caution||Suitable|
Note: The shape of the nozzles above is for illustration purposes only and may differ.
Red cross: Not recommended. Green check: Suitable. Orange check: Use with caution.
- 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: Stay prepared for any job with Simpson ALH4240's handy storage area, which allows you to neatly store any nozzles and accessories which you may need for the job.
- 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, pressure regulator, oil, wand, spray gun and pressure hose.
- Emissions: The Simpson ALH4240 is NOT CARB-compliant. Thus, it cannot be purchased or sold in California.
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.
- The Simpson ALH4240, which can reach up to 4200 PSI, has one of the higher pressure outputs of the gas-powered units that cost between $1000 and $1400. If the highest possible power of the water stream is your priority, one of the champions in this price range is the Lifan LFQ4515E-CA with 4500 PSI.
- With a water flow of up to 4 GPM (gallons per minute), this washer belongs to the best of the above-mentioned price range, as it can deliver a high volume of water.
- With a rather impressive value of 16800 Cleaning Units (PSI X GPM), the ALH4240 has a higher cleaning efficiency compared to similarly priced devices. In case you are looking for the highest overall cleaning power, in this price range, one of the current champions is the Lifan LFQ4515E-CA and its 18000 Cleaning Units.
As you can see from this interactive chart, 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
- Triplex pump
- Honda engine
- Designed to be stable
- Aluminum frame
- Good range of nozzles included
- Onboard storage
- Several security features
- 10 year (limited) warranty
- High PSI for the price
- High GPM for the price
- High CU for the price
- No soap tank
- Not CARB-compliant
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.
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.