How To Choose The Best Replacement Pressure Washer Pump

A pressure washer is a great way to clean your outdoor living space and vehicles with saving a lot of time. But, when your pressure washer becomes unable to blast away dirt and grime it might have some problem. And the reason is sometimes your pressure washer’s pump.

Now the chances are you have to change and replace your pressure washer’s pump. And you know without the right pump, your pressure washer can be ineffective. So whether you need a replacement for your pressure washer pump or just want to stay informed, here’s how to choose the best option for your needs.

How To Select The Perfect Pressure Washer Replacement Pump

A pressure washer pump is an integral part of your pressure washer and can determine performance and longevity. They are the heart of the power washing system, so it is important to choose a good quality pump for your pressure washer. 

There are many different types of pumps on the market, but not all will work with your specific model or brand. Choosing a replacement pump can be difficult without doing some research first. 

Here I will explain how to choose the right replacement pump to fit any brand or model of pressure washer. This includes some tips for maintaining your pumps. But first, know about some types of pressure washer pumps.

Pressure Washer Pump Types (Most Common)

There are several types of pressure washer pumps in the market. The most famous and widely used pumps are discussed here in brief:

Axial Cam (aka Triplex)

This is the most common type found in consumer-grade electric and gas-powered pressure washers. Usually located near the trigger of the unit. They’re relatively inexpensive, but do require some regular maintenance to keep them running smoothly. 


This is a custom-type pump used on some more expensive brands of commercial pressure washers. They are usually located under the engine or near it on top of the frame. This style pump does not need any regular maintenance and has an air-cooled motor for less vibration noise than other pumps.


Compressors for this type of pump are usually located underneath the frame of your pressure washer. It’s considered a more “premium” pump because it is extremely durable and can handle high PSI, high temperatures, dirty water, etc… without any real maintenance in the long term. 

Rotary Vane

This is an oil-less design that runs at very high speeds to generate pressure in minimal time when compared to other types of pumps. These are most often found on professional-grade electric power washers for commercial use.

Pump Water Flow Rate & How Pressure Washers are Rated

The specifications you see when shopping around for a replacement pump are typically rated in gallons per minute or GPM (flow rate). The most common you’ll see for electric power washers is around 1 GPM and 1000-3000 PSI, and for gas models, it may be as high as 2.3 to 5 GPM and 2500 to 8000PSI.

It’s important not to sacrifice too much pump flow rate on your electric pressure washer because even though the unit may work fine at lower GPM, it will have more of a strain running at that speed all of the time which can lead to premature wear on the pump.

How Much Pressure Do I Need?

The amount of pressure you need depends on what type of cleaning jobs you’ll be using your machine for primarily. If you’re doing a few types of jobs or have occasional needs for residential-grade units, then it would probably be best to get a machine that’s around 2,000 PSI (or more) at 1.5 GPM.

Most homeowners need only up to 1500-2500 PSI for general household use like driveway cleaning, deck washing, and car cleaning. This is because they don’t usually have the higher psi dirtier jobs frequently.

Choosing A Best Fit Replacement Pump For Your Pressure Washer

When looking at specific pumps to buy, you can choose one by matching your pressure washer brand or model to see if it fits directly or is compatible with your unit.

Keep in mind that many of the pumps available are universal fit options designed to fit multiple models without needing to buy a specific brand replacement pump. 

Find Your Model Number and Type – Step 1

If you know your pressure washer’s specific model number, then finding the correct replacement pump is simple. If you’re not sure, then take apart your pressure washer to see what type of pump it has.

Gas-powered units typically have axial cam or compressor pumps.

Electric units will either have axial cam or diaphragm pumps. 

Find Out What PSI & GPM Rating You Need for Your Unit – Step 2

Find the PSI and GPM  of your old pressure washer pump. Your current pump’s PSI and GPM must match that of a replacement. Do not assume that more GPM and PSI are always doing better. You should not buy a new pump with higher PSI, since it can either slow your engine down or It can also surpass the maximum burst pressure your hose can handle.

Check For The Accurate Measurement Of Your Old Pump – Step 3

Now check the exact measurement of your pressure washer’s old pump by getting help from the owner’s manual. Compare these measurements with the ones you are going to order and replace. Double-check the measurements!

How to replace a pressure washer pump? 

Now that you have chosen the right pressure washer pump replacement for your precious machine, it’s time to change it. You can see our complete guideline about changing a pressure washer replacement pump in the below-linked article.

How to Install a replacement pressure washer pump.

Flinn Milan

Flinn Milan is the content director at Washwith. He is responsible for developing helpful content in collaboration with other hard-working team members. Over several years, his content strategy is mainly focused on describing and highlighting every product with its positive and negative points

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