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Can You Install a Bigger Pump on a Pressure Washer?

If you’re wondering if the current cleaning capability of your pressure washer lies short of what you require, consider installing a bigger pump on your pressure washer. If you’re unsure how to do it, read this blog post.

Can you install a bigger pump on a pressure washer?

Three things must be considered to install a bigger pump on a pressure washer. The first thing is to check that the engine is compatible with the new pump, i.e., it provides the necessary horsepower for the pump to operate effectively. Secondly, ensure that the couplings or interfaces of the new pump can be made with the rest of the pressure washer. Lastly, the pump’s placement and mountings must be made to fit securely within the pressure washer and not vibrate.

How can we calculate the horsepower we need to maintain our present PSI? This article will give you all the knowledge you need to upgrade your pressure washer pump, regardless of whether you’re a house owner or an expert cleaner.

How Much Horsepower Does a Pressure Washer Pump Need?

The horsepower requirement for a pressure washer pump depends on the pump’s PSI rating and the mass flow rate (GPM). Most standard pressure washer pumps require around 1-8 horsepower (HP). For industrial uses, the HP requirement is greater than 11 HP.

Engine horsepower is a critical factor to consider when buying a pressure washer. It ultimately determines the pump’s performance parameters, such as the output pressure (PSI) and the mass flow rate (GPM). Both of these variables influence the cleaning capability of a pressure washer.

How do I calculate HP?

The requirement for horsepower depends on the requirements for maximum pump pressure (PSI) and the mass flow rate of the pump in gallons per minute (GPM). Then, the minimum horsepower required for the engine to obtain the desired performance parameters can be calculated as:

Horsepower required (HP) for electric motors = (Mass flow rate (GPM) x Pressure (PSI))/1460

Horsepower required (HP) for gas engines = (Mass flow rate (GPM) x Pressure (PSI))/1100

– Example:

For example, if a pump delivers 3000 PSI pressure and 2.5 GPM mass flow rate, the required horsepower value is 5.14 HP for an electric motor. You would need a 6.8 HP gas engine to power the same pump. This is typically due to mechanical losses and inefficiencies that play a much more significant role in gas engines than electric motors.

The typical HP values for most domestic pressure washers lie around 1-8. For commercial washers, this value may exceed 11 HP. A larger HP requirement increases the engine size. This makes the machine bulkier and adds to the fuel and operating cost requirement. Hence, running a high-performance pump would be costlier than a low-end pump.

Other than HP required, the pump’s frame, build quality and the material used should be considered when buying a pressure washer pump. Having plunger pumps made of ceramic materials and lightweight frames have a longer running life (more than 2000 hours)

Can A Pressure Washer Be Too Powerful?

If you purchase a pressure washer without considering your required PSI, two possibilities could occur. If you buy a pressure washer that produces less pressure, you would spend more time cleaning. However, if you get a pressure washer that is excessively powerful—too powerful for your type of project, you risk causing damage to your property.

In the second case, you risk spending far more on equipment than you need. We believe you should start low and gradually increase your PSI if you are unsure how much you need. Although this advice is somewhat valid, it could result in overspending, a waste of money.

Continue reading to learn how much PSI of pressure washer you should use for a specific cleaning task to prevent inefficient washing, property damage, and wasted money.

  • Light-duty chores: A pressure washer with a 1-2 horsepower motor can be used to clean automobiles, porches, and other open spaces.
  • Medium-duty chores: A 2-4 HP pressure washer can be used for medium-duty activities like cleaning walkways and cement.
  • Tough jobs: A pressure washer with a 4–8 HP motor is required for tough jobs like paint removal or cleaning huge commercial spaces.

If you work in the building, food service, trucking, or any other business or need an industrial cleaning solution, a 4000 PSI power washer is the best choice.

Are All Pressure Washer Pumps the Same?

No, pressure washer pumps differ significantly. There are various pressure washer pump types, each with unique features and capabilities. Let’s look into each of them:

1. Wobble Plate Type

Wobble pressure washer pumps are the least expensive. They are also known for being the lightest-duty washer pumps. A wobbling pressure washer pump typically lasts 200–400 hours. It is less effective than the other pumps since it must work more to push through water and two springs. Wobble pumps are usually irreparable.

2. Axial Type

With better design and lifespan and more GPM output and PSI flexibility, axial pumps are a step above the Wobbling type. Axial pumps are the industry standard for household to prosumer pumps. Generally, an axial pump will operate 500–800 hours longer than a wobble pump, lasting 2-3 times longer. Even while axial pumps are more durable than wobbling pumps, they still have more resistance than Triplex pumps.

3. Triplex Plunger Type 

Compared to Axial and Wobble pumps, Triplex pumps are more environmentally friendly. They also provide the greatest PSI and GPM output versatility, allowing greater PSI and GPM setups. Moreover, they can be repaired. A Triplex pump can indeed outperform an axial pump by ten times. The triplex pump operates by a crankshaft operating piston to draw in and release out water.

Selecting the best kind of pump for your particular requirements and financial situation is essential. While selecting a pressure washer pump, you should also consider the pump’s material, the size of pistons or cylinders, and the drive type (direct drive or belt drive).

Can You Replace an Axial Cam Pump with A Triplex Pump?

Replacing an axial cam pump with a triplex pump on a pressure washer is often possible. But, the pressure washer’s structure, motor, or plumbing might require adjustment or modification.

  • Engine compatibility: First, the triplex pump must be tested to ensure it is interoperable with the engine or motor powering the axial cam pump. Triplex pumps are stronger and more reliable. They need more powerful motors, three pistons, and plungers to generate more PSI than axial cam pumps.
  • Connections: Confirming that the pressure washer’s piping and hoses work with the new pump is crucial. Modifying your piping and fittings to maintain optimum flow and pressure would be best since triplex pumps often require bigger hoses and connections than axial cam pumps.
  • Mounting: The mounting arrangement of the triplex pump must next be analyzed and matched with that of the axial cam pump. You can switch the axial cam pump to the triplex pump without adjusting if the mounting holes and bolt pattern are the same. But, if the mounting arrangement differs, you might need to modify the pressure washer’s frame or pipes to create room for the new pump.

What Type of Pump Is Best for A Pressure Washer?

Axial, Triplex, or wobble pumps are the three options available when selecting one for your power washer.

 A triplex plunger pump is probably the best choice for those seeking the best service and long-lasting pump for the pressure washer. Axial cam pumps are direct drives, rotating at the same rate as the engine. They offer a lot of pressure and performance but will degrade more quickly than a triplex pump.

Yet, Triplex plunger pumps are the best pressure washer pumps available since they have a longer lifespan and function better. These also come with a higher price tag, but if you plan to use your power washer frequently, the extra money is well spent. Also, you can have the pump rebuilt rather than purchasing a new washer if the pump malfunctions.

However, it’s critical to select a pump that satisfies your different speed and power requirements, is compatible with the piping and engine or motor of your pressure washer, and meets those standards.

What Is the Difference Between Piston and Plunger Pumps?

Both piston and plunger pumps use a reciprocating mechanism and are driven by a rotating crankshaft. The location and functionality of the seals or O-rings are the major difference between piston and plunger pumps.

But how do those variations impact the pump’s functionality? It can significantly affect the following things.

1. Pressure Capacity:

  • In piston pumps, the piston head fits tightly in the cylinder head, and the pistons move with the head in a reciprocating motion. A reciprocating rod must be sealed against the cavity wall to prevent compression loss in a piston or plunger pump. The entire seal is connected to the piston head in piston pumps, moving back and forth. Hence, the sliding action of the seals generates more friction in the case of piston pumps.
  • In plunger pumps, the plunger fits loosely in the cylinder. Also, the seals are stationary, due to which lesser friction is produced. Hence, the sliding action is smoother with a plunger pump. Because there is less friction, the motor doesn’t have to work as hard to generate more force. Therefore, piston pumps can produce higher pressure ratings against the same engine/motor.

2. Durability of Materials:

The plunger in a plunger pump must seal against the cavity of the cylinder walls. Hence it must be manufactured from tough materials such as stainless steel, brass, or ceramic. In a piston pump, the hollow walls must seal against the rod with the O-ring, which means the cylinder wall must be designed to be as tough as possible.

Note that it’s much harder to manufacture a hollow casing from a hard material than a cylinder. Plungers can be manufactured more easily than the housing of a piston pump. Due to this reason, plunger pumps can be made more durable than piston pumps.

3. Need for Maintenance:

The need for maintenance increases as the number of parts increases. Plunger pumps are much easier to maintain than piston pumps because they have a simpler design, fewer parts, and a simpler construction.

4. Cost Factor:

When comparing pumps with equal performance, plunger pumps might be far less expensive upfront. Their overall cost of ownership is often lower as well, particularly when you consider future maintenance, fixes, or replacement. Also, their ease of manufacture lowers the per-unit cost when assembled.

What is a Quintuplex Pump?

Quintuplex pumps are reciprocating pumps with five connecting rods to drive the pistons/plungers. These pumps offer a smooth mass flow rate at the output.

A driveshaft drives the pistons/plungers via a connecting rod in reciprocating pumps. In duplex pumps, there are two connecting rods and two plungers/pistons; in triplex pumps, there are three.

Quintuplex pumps have five connecting rods, and piston/plungers are driven simultaneously by the drive shaft. This type of arrangement results in the least fluctuations in the mass flow rate at the pump output. Also, quintuplex pumps can handle large flow rates with the least fluctuations while maintaining higher pressures. Such pumps are commonly used in water purification, desalination plants, and oil transfer sites.