Simpson MegaShot MSH3125 pressure washer review

We review the Simpson MegaShot MSH3125 pressure washer, a gas-powered model aimed at the domestic market.

Simpson MegaShot MSH3125 pressure washer review: Image shows the pressure washer against a white background.
(Image: © Amazon)

Top Ten Reviews Verdict

The Simpson MegaShot MSH3125 pressure washer is near the top of its class for value for money. With a powerful PSI/GPM ratio and a 5.2HP engine, it’s a good choice for homeowners who need the flexibility of gas over electric.


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    Sturdy and reliable

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    Easy to store


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    No integral detergent tank

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In the market for a new pressure washer? It can be hard to decide what the best pressure washers are for your personal requirements, so we’ve done some research on the Simpson MegaShot MSH3125 pressure washer for you. We’ve included dimensions, pros and cons, and what users really think about it. 

This sturdy workhorse of a patio washer is sold for domestic use, making it suitable for cleaning cars, decking or driveways, blasting grease off the barbecue, cleaning patio furniture, or preparing surfaces to be painted. Gas-powered washers are normally more powerful than electric versions, and this washer packs quite a punch at 3200 PSI and 2.5 GPM. It comes complete with engine oil, on-board storage, hose, and a set of five nozzles (0°, 15°, 25°, 40°, and soap) to tackle a wide range of jobs. As a gas-powered model it’s more portable than electric and can be used anywhere outdoors (don’t use it inside due to the fumes!), but it’s also heavier, louder, and less environmentally friendly. On longer jobs, you’ll have to keep refilling the fuel tank too, which can be inconvenient. The GC190 engine (approximately 5.2HP) is made by Honda and the tank holds 0.48 gallons which is fairly typical for models of this size. It has a recoil start, a simple and generally safe system which means you have to pull a handle to start the engine, a method used by all sorts of appliances including lawnmowers. 

Simpson MegaShot MSH3125: Essential info

Weighs 66lb 

Costs around $400

25 foot hose 

0.48 gallon gas tank

GC190 Honda engine

5 nozzles and built-in storage

Warranty from one to five years on different parts

Maximum pressure 3200 psi, GPM 2.5

Pneumatic 10” wheels

Recoil start

It doesn’t come with a built-in detergent dispenser, but you can connect it to an external bottle. You’ll also need a water faucet. 

The Simpson MegaShot MSH3125 pressure washer costs around $400, which is at the lower end of the price band for its capability (prices for gas pressure washers range from around $300 for an entry-level domestic model to $1,400 for a commercial model). The warranty is complicated but comprehensive – a two-year limited consumer engine warranty, one-year limited pump warranty, five-year limited frame warranty and 90-day limited accessory warranty, which all adds up to fairly standard cover. One thing to note is that it’s not available in California as it’s not CARB compliant, meaning that it doesn’t meet the required standard in that state for harmful emissions, toxins and particulates. Gas washers in general aren’t as eco-friendly as their electric cousins, so if environmental concerns are a priority then it could be worth checking out electric washers. 

Simpson MegaShot: How big is it?

  • Height: 24 (in)
  • Depth: 34 (in)
  • Width: 21 (in)

The Simpson MegaShot MSH3125 pressure washer is good value for money, offering a decent ‘power for your dollar’ ratio.  

This washer is aimed at the domestic market, making it suitable for most maintenance jobs. As it’s a gas model, it’s easy to move it around, which is practical if you have a long driveway and need to wash both ends! Larger projects will require you to refill the gas tank – although there’s no manufacturer’s standard, users report getting around one to two hours use out of one tankful.

Simpson MegaShot MSH3125 pressure washer review

(Image credit: Amazon)

Simpson MegaShot: Functions and features

This washer has a GC190 Honda engine, equivalent to 5.2HP. The pump is axial, which is a direct drive pump spinning at the same speed as the engine. These are a mid-range pump, better than cheap wobble pumps but less robust than the triplex plunger pumps which are found on commercial units. The good news, though, is that these pumps can be replaced when they reach the end of their life so you don’t need to replace the whole unit. The washer has pneumatic wheels and comes with 25 feet of hose. It has a PSI of 3200 and delivers 2.5 gallons per minute, which is powerful for a unit of this price range.  

Accessories include five quick-change nozzles, wand and engine. 

Simpson MegaShot: What’s good about it?

The value for money! It delivers a weighty power punch for your money and should cope with most domestic jobs with ease. No electric cord means you can move it around your property as required, although you will need access to a water faucet. 

It’s sturdy and robust and although it’s not lightweight at 66 lbs (most gas models do weigh in around this mark), users have reported that it’s relatively easy to move around on pneumatic tires. 

Simpson MegaShot What’s not good about it?

The cover is a little confusing as different parts are subject to different warranty lengths. The RYOBI RY803001 3000-PSI Power Control, for example, which is comparable for price and performance, has a blanket three-year warranty. The Simpson MegaShot MSH3125 pressure washer has a two-year limited consumer engine warranty, one-year limited pump warranty, five-year limited frame warranty, and 90-day limited accessory warranty which could lead to you forgetting what’s covered when. 

There’s no integral detergent tank, so you’ll have to take a separate container with you when you start your project. 

Simpson MegaShot MSH3125 pressure washer review

(Image credit: Amazon)

Simpson MegaShot: How efficient is it?

On the whole, gas pressure washers are less environmentally friendly than electric models. That said, pressure washing is an eco-friendly form of cleaning – it’s efficient, uses much less water than a hosepipe and can be done with no chemicals. This model has a high PSI and GPM output so will clean quickly and efficiently. 

Simpson MegaShot: User reviews

This pressure washer has worked great for me so far. Used it the first day for about six hours on my home and driveway. Did the simple oil change and have used it three times since.

HomeDepot reviewer

An impressive 88% of over 4,500 HomeDepot users would recommend this washer, and it scored 4.5 stars overall. Users picked up on a couple of potential issues, saying that the hose was stiff and hard to manage. The latest reviewers have also mentioned that the product was oily on arrival – this seems to be a recent issue which the company is working to resolve. Overall, customers were happy with their purchase, commenting that it was powerful, easy to use, and that the motor started reliably on the first pull.

Should you buy the Simpson MegaShot MSH3125?

The Simpson MegaShot MSH3125 pressure washer is good value for money in its category. It’s a good choice for most homeowners, but if you live in a suburban area then you might prefer a quieter electric version such as the Stanley SLP 2050 2-in-1 pressure washer

This model comes with impressive user ratings and will tackle most domestic jobs with ease. 

Sara Walker

Sara is an experienced magazine journalist and commercial copywriter. Writing helpful home-related content for Top Ten Reviews, Sara splits her time between the UK and France, alongside her Springer Spaniel.