Simpson Powershot 4200 psi Pressure Washer Reviews

Simpson Powershot PS4240 Pressure Washer Review

Pressure Washers

Build Quality
Feature Set
Ease of Use
Final Thoughts

With the Simpson Powershot PS4240 pressure washer, you get a huge pump that supplies the 4.0 GPM of water, blasting away everything at 4200 psi. You can also count on the Honda GX390 to start every time.

Overall Score 4.4 Final Thoughts

Living in Central Florida can be likened to living in an armpit. Okay, maybe this needs a little explanation. Our humidity during the Spring and Summer months hovers around 100%. Temps in the 90s and that humidity level, heavy sweating is in the forecast. With this environment, mold and mildew will grow on anything. Enter the Simpson Powershot PS4240 pressure washer to save the day.

Delivering 4200psi to the tip, the Simpson PS4240 powers through about anything in its path. Supplying the water to the wand is a 4.0GPM AAA industrial triplex plunger pump. Driving the pump is the tried and true Honda GX390 gas-powered engine.

Our testing and review location lies in wait, just next door. A large screen enclosure covers a pool, hot tub, and outdoor patio. From the looks of it, this lanai hasn’t been touched by any cleaning in well over a year. All the white aluminum is covered in green splotches along with much of the faux rock around the pool’s edge.


Simpson  Powershot Build Features

Build Quality

Simpson PS4240 Tubular Frame

Simpson PS4240 Tubular Frame

The frame of the Simpson PS4240 is built from 1″ tubular steel and welded plate. A steel axle provides support for the pressure washer and connects the two 13-inch rubber tires. The powder-coated matte black finish helps to keep water and chemicals from rusting and corroding the steel. The handle used to lift pull the pressure washer around is bolted on with two thumb screws. These thumb-screws make it easy to remove, hence providing a more compact footprint for storage.

Related Article: Different Ways to Use Your Pressure Washer

In addition to providing the rigidity, the tubular frame is built in such a way that acts like a roll-cage. The front of the Honda GX390 engine, the rear of the pump, and even the top around the gas tank receive protection from this tubular frame. Quality components surround this Simpson Powershot PS4240, such as the Honda powerplant, AAA pump, steel wheels and pneumatic tires, Monster Hose, and many brass fittings.

Simpson Powershot PS4240

In-Use and Testing

Green Florida Living

Green Florida Living

As mentioned prior, or testbed includes a ton of mold and mildew on a white aluminum pool cage. In addition, the patio surface was in dire need of a deep-clean with years of crud built up. We intentionally left off the chemicals this time, just to give the Simpson PS4240 the opportunity to knock it all out – on its own. Impressively, it did!

From the first start-up, the Honda GX390 roared to life without hassle – imagine that, from a Honda (sarcastic). At first pull of the trigger, it was evident that a plethora of power was flowing past the tip. It was more than a few times that one of us thought we were being launched into the pool. This may sound a bit exaggerated, but when you’re reaching high, bending over, or your footing isn’t the best, the force of the blast can quickly affect the situation.

Pro Tip: Be careful when climbing ladders with a pressure washer wand in your hand. Remember Newton’s third law: For every action, there is an equal and opposite reaction. The same amount of force being pushed out that tip is being pushed against you. I’ve had first-hand experience at watching someone play Superman from the ladder as they pulled the trigger on the wand. They only wished they were the man of steel when they hit the ground.

Quality Brass Fittings

Quality Brass Fittings


AAA Pump Oversized Bearings

AAA Pump Oversized Bearings

It’s evident from the work being done at the business end, there must be ample power pushing. The Honda GX390 produces almost 12hp from the 389cc displacement. Probably more important is the 20lb-ft of torque from the powerplant at 2,500 rpm. When the pressure’s on (pun intended), it’s the torque that matters. Moreso, the engine includes a low-oil shutdown to mitigate any engine failures.

AAA Industrial Pump – 4.0 GPM 4200 PSI

Pumping the water is an AAA Industrial triplex plunger pump which is direct-drive to the Honda powerplant. The AAA 90034 pump is rated up to 4200 psi at 4.0 GPM, and AAA pumps carry a 5-year limited commercial warranty. Dual oversized ball bearings provide better wear and friction resistance, providing longer lasting performance.

While you should read the user manual before using your Simpson Powershot pressure washer, they provide the multi-step startup sequence right on the machine. Always remember with a pressure washer, especially with a direct-drive pump, hook up the water supply first. Turn the power switch to the “on” position, close the choke, turn on the gas, and pull the cord. The Honda GX390 starts with ease. Time after time, the engine starts without issue. You can release pressure on the hose before starting to make starting even easier.

Green Grime - Gone

Green Grime – Gone!


Ergonomic Handle

Ergonomic Handle

Using quality components sometimes comes at a cost – or costs. Weight typically goes up with quality, so the Simpson Powershot PS4240 is not a lightweight. Simpson does a great job with other features to help distribute the weight proportionally and ease transport.  The large 13-inch pneumatic tires and the large offset-tubular handle make moving the heavy PS4240 very easy.

Included with the Simpson Powershot is a 3/8″ diameter hose with a length of 50-feet. The Monster Hose is abrasion resistant and includes quick connect couplings on each end.  Also, the spray-gun (wand) has an ergonomic design for better control and comfort.  We really liked the full-length trigger and the bold lockout. This spray-gun is easy to hold, and the other end offers an area for your additional hand.

Blasting It All Away

Simpson includes other niceties with the Powershot PS4240 that just make it a better overall experience. Five quick connect nozzle tips are included, and they fit snug in a rubber seat on the main-frame. These tips are 0°, 15°, 25°, 40° and Soap-tip. In addition, the spray-gun has a mount on one side, and the opposite includes the mount for the 50′ hose.  We’re kinda big on calling those out that don’t provide a place for everything. It seems that Simpson has done a great job at keeping everything in one package.



The Simpson Powershot PS4240 pressure washer is one of those tools that can bridge the gap for the novice. At least it did for us! It performed so well, it made us look like pros. We used the 25° and 40° tips for most of the work on the patio. The pressure was more than ample to take care of all the filth, hence turning it back to the white aluminum it’s supposed to be. Even blasting grime out of the crevices in the rocks was no match for the Simpson Powershot.

Simpson Powershot 4200 psi

Simpson Powershot 4200 psi

With the GX390 12hp engine and 4.0 GPM pump, this is the most powerful pressure washer you can get before moving to a belt-driven pump. It will be hard to find a more powerful machine with this small of a footprint. We didn’t use the siphon hose for any chlorine or soap since we were intentionally testing otherwise. The siphon hose is included with the Powershot pressure washer, and the port is located right on the pump.

Impressive Results

We were impressed with how well the Simpson pressure washer handled everything we threw at it, and it never had a hiccup. We even ran it out of gas at one point. A quick fill-up and we were back up and running. It’s easy to recommend a machine like this. Performance speaks for itself, and the notable quality components stand on their own as well. So where’s the catch? – it can’t be all lollipops and rainbows! Remember back when I said that quality comes at a cost? It literally does. Buying this Powershot PS4240 will set you back about a grand. Even so, we still recommend this machine, as long as you’re willing to pay the price.

Click here to find out more about the Simpson Powershot PS4240 Pressure Washer.

0°, 15°, 25°, 40° and Soap

0°, 15°, 25°, 40° and Soap Nozzles


Simpson PS4240 Pressure Washer Specifications

  • Honda GX390 12HP Powerplant

    Honda GX390 12HP Powerplant

    PSI: 4200

  • GPM: 4.0
  • Engine: HONDA GX390 engine with low oil shutdown
  • Pump: AAA Industrial triplex plunger pump
  • Pump/Hose Connection: Quick connect
  • Hose: Monster Hose 3/8″ x 50′ steel-braided hose
  • Gun/Hose Connection: Quick connect
  • Wand: 31″ Steel with quick connect and threaded M22 connection
  • Nozzles: 0°, 15°, 25°, 40° and Soap
  • Frame: Heavy duty welded steel construction with steel axle frame
  • Tires: 13″ Premium pneumatic
  • Price: ~$1,100
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Noah Liguori

Is this engine actually American made…or made in China? Also is the 4200 worth the extra cost and noise? (I have lots of exposed aggregate driveway, Allan block planters, stucco house railings etc. Thanks