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How do I know if my pressure washer pump is bad?

A pressure washer is a helpful tool that effectively cleans your patio, driveway, car, and other objects. However, wear and tear over time can affect your pressure washer’s performance. The pump is one of the most common parts of a pressure washer that malfunctions.

How do I know if my pressure washer pump is terrible:

Several indicators will show a faulty pressure washer pump. The most common is a leak, pulsating output pressure, and low output pressure. A worn or damaged pump seal often causes leaks. A pulsating pressure indicates that there is not enough water in the pump. Low pressure is generally due to worn O-rings or a dirt blockage at the pump inlet.

This article will explain how to diagnose a pressure washer pump fault quickly. I will list the indicators of a faulty pump and the reasons behind the pressure washer pump failure.

Contents

Faulty Pump indicators

Here are the most common pressure washer pump failure indicators:

1. Faulty Pump indicator: Leaks

Leaks are probably the most common problems associated with pressure washer pumps. Leaks are often caused by a damaged or worn seal. A leaking indicates a worn O-ring or gasket. Replace the old gasket with a new one to fix the leak.

A leaking cylinder head or inlet/outlet elbow is often caused by frozen water inside the pump. Before the winter hits, you need to drain all the water in the pump. Otherwise, it will expand and damage the plastic parts. Tighten the gold parts if necessary.

To identify leaks, remove the case of the pressure washer and turn the water on. Please do not turn on the motor or engine with its topic removed. Water flowing from the hose will run through the pump, indicating where the leak originates. Check the water inlet and your spray tip for any issues.

2. Faulty Pump indicator: Pulsating output pressure

The main reason for the output pressure to pulse is an insufficient inlet water supply. In the case of an electric pressure washer, this results in the motor restarts. Remove the inlet filter and clean any blockages.

If this is not the cause, there can be a blockage in the pump, or a leak from the cylinder head can also cause the pressure to pulse. Feel free to check other pressure washer troubleshooting resources if needed.

3. Faulty Pump indicator: Low output pressure

A pressure washer not producing enough pressure also indicates a fault in the pump. Low pressure is due to a worn-out O-ring or a rubber gasket that seals the inside of the pistons and valve. To fix the issue, replace the worn O-ring.

Low pressure can be due to dirt blockage if the seal is fine. To restore the machine’s pressure, clean the filters and remove the dirt and debris that prevent adequate water supply to the pump. Our troubleshooting blog covers a wide range of topics that might help.

From my experience, I recommend servicing the pressure washer pump every three months or after 500 hours of use, whichever comes first. Regular servicing can significantly extend the life of your pump.

How do you test a pressure washer pump?

Turn on the pressure washer pump to troubleshoot or test a pressure washer. Use the pump problem indicators to diagnose the issue. Different types of problems arise because of the failure of other parts in the pump.

The table below will help to interpret and analyze which part of the pump is causing the problem. Once you have tested and found the root of the problem, use the table to fix the problem. Refer to our pump fitment chart for more details.

Tips to remember when you purchase a new pressure washer: The key to maintaining your engine and pump is regular maintenance and monitoring the water temperature. Always be mindful of issues with your pressure washer; feel free to consult professionals if needed.

Remember to tighten the loose parts and regularly check your pump’s condition. Always be careful with your pressure washer, and happy cleaning!

Problem
Causes
How to fix
No pressure
The pump inlet valve damaged
You need to disassemble the pump and clean the inlet valve. If the problem still occurs, you need to replace the inlet valve.
Unloader valve damaged
To fix this problem, adjust the unloader screw. Also, check for damaged seals and springs.
Inconsistent pressure
The pump inlet valve was damaged
Sometimes, we receive pulsing pressure from the washer outlet, which means pressure constantly gets high and low. This problem can be fixed by cleaning or replacing the inlet valve.
Faulty Pump
Replace the pump.
Air sucking pump
To fix this problem, turn off the washer and release the pressure inside the pump by squeezing the trigger gun.
Problem
Causes
How to fix
Water leaking pump
Worn or damaged seals
Change the seals.
Excessive Noise
Low level of oil in the pump
Disassemble the pump and check the oil. If the oil level is low or the oil is cloudy, remove the old oil and refill the oil tank.
Oil leaking pump
Damaged seals, gaskets, or pistons
Disassemble the pump and check the seals or pistons. If they are worn or damaged, replace them.
Loose fittings
Oil may also leak due to loose bolts and fitting of the pump assembly. Check the pump assembly and tighten it if it is loose.
Low pressure
Insufficient water supply
Ensure adequate water supply to the washer by unkinking the hose or using a hose with a large diameter (3/4 “recommended).
The inlet filter was blocked due to dirt and debris
Cut off the water supply and clean the filter.
Worn-out nozzle
Change the nozzle and make sure that you use the correct one.

Why does the pressure washer pump fail?

The life expectancy of all pressure washer pumps is pre-defined. The reason for pressure washer pump failure is not always natural wear and tear. A faulty unloader valve, cavitation, and water overheating can be other big reasons behind pressure washer pump failure.

● Cavitation

One of the more common problems that occur because of low water supply pressure is cavitation. Air cavities, or air bubbles, form inside the water supply and can cause a loss in capacity and water pressure and a drop in efficiency.

The pressure washer becomes noisier and vibrates more when the water inside the supply becomes saturated with air cavities. The cavities leave low-pressure areas and pass into a high-pressure region. Cavitation can even cause a small explosion that damages the pump.

Cavities are formed for different reasons. The most common sense for cavity formation is an insufficient water supply. The water supply flow should always match the pressure washer’s Gallons Per Minute (GPM) rating. Vaporization is another cause of cavitation in the pressure washer pump.

It occurs due to the high temperature of the water inside the pump. Another cause of cavitation is air ingestion. Air ingestion can also cause damage to the pump of the washer. However, its consequences are less severe than vaporization.

● Water Overheating

The pressure washer pump builds pressure even when you are not spraying. When you stop squeezing the trigger, the pressure built by the pump is not relieved, and pressure continuously builds inside the pump. Unrelieved pressure does not damage the pump.

This is because the unloader valve, also known as the thermal release valve, activates when you do not squeeze the trigger for some time.

The unloader valve diverts the water flow in a loop to the inlet. The pressurized water is depressurized in the bypass inlet and is fed to the pump again. This cycle continues until the water is released. The unloader valve protects the pump with its bypass mechanism.

However, you should not test its limits for too long. Overheating happens when the pump is in bypass mode for too long. When the same water is cycled through the pump, it gets warmer as the crankcase generates heat. If this water gets overheated, it can damage the pressure washer’s pump.

– Recommended Duration for Water Cycling in Bypass

Manufacturers allow up to 2 minutes for the water to cycle in bypass, but we recommend not letting your pressure washer run for more than 45 seconds without squeezing the nozzle. If you need to wait longer than that, you must turn off the washer and restart it when you are ready to use it.

The two most common reasons the pressure washer pump goes bad are a faulty unloader valve and a clogged carburetor (gas-powered washers).

Continuing to use a pressure washer with a bad pump can lead to inefficient cleaning, further damage to the pump, and potential safety hazards. It’s always better to address issues as soon as they arise.

● Unloader valve

Many pressure washer problems start and end with the unloader valve. This critical pressure washer component controls the pressure. When the trigger is released, it diverts the water flow into a loop to retain high pressure.

When you hear sputtering sounds coming from a gas pressure washer and the engine stalls, it means that the unloader valve of the washer has been damaged, probably due to an increase in the pump pressure.

The piston controls pressure retention and is one of the essential parts of the unloader valve. The piston moves back and forth when the pressure washer is operating. When this movement is stopped or interrupted, the pressure washer stops. Remove the piston from the unloader valve and inspect it.

The pressure washer can also stop when the trigger is pulled due to worn-out or cracked O-rings. This can cause leakage at the pump and prevent the unloader valve from working correctly.

As a result, the pressure washer stops when the trigger is pulled. Check the O-rings of the unloader valve and replace them if they are cracked or damaged.

– Consequences of a Malfunctioning Unloader Valve

If the unloader valve is not working correctly, it can damage the pump. This happens when the unloader valve does not allow the water to divert in the loop to the inlet to release pressure. This builds up the pressure in the pump. The pump is affected when the piston takes longer to divert the water flow.

Adjust the settings so the unloader valve can divert the water back to the inlet to avoid pressure build-up that can damage the pump.

Is a pressure washer pump protector necessary?

I recommend using a pump protector in cold weather and before storing your machine for an extended time. It is not necessary to use a pump protector after every cleaning job.

When the pressure washer is stored for an extended period, the water and moisture left inside the pump can cause corrosion, mineral deposits, and sticking of the valves. I recommend protecting the pressure washer pump in cold weather and for long-term storage.

At temperatures below freezing, the water inside the pump will freeze and expand, damaging and even cracking the pump.

A good solution is using a pump protector. To prevent sticking, the pump protector adds lubrication to the valves, pistons, and seals. Some manufacturers recommend applying a pump protector after every use. I do not think this is needed. It is costly and does not give additional benefits.

I recommend using a pump protector when you are going to store your equipment for the winter season.

● How to use a pump protector?

Use the following steps to use a pump saver/protector.

  • Step 1: Turn off the engine/motor
  • Step 2: Disconnect all the hoses.
  • Step 3: Open the bottle of the pump protector by unscrewing the top and removing the internal seal.
  • Step 4: After removing the seal, close the bottle again.
  • Step 5: Remove the protective cap at the top of the covering to expose the male garden hose thread.
  • Step 6: At the pump inlet, screw the pump protector bottle into the hose fitting.
  • Step 7: Inject the pump protector fluid into the pump by squeezing the bottle.   
  • Step 8: For gas-powered pressure washers, pull the starting cord until the pump protector fluid is released from the outlet. Turn on the pressure washer for electric pressure washers until the pump protector fluid is discharged from the outlet.
  • Step 9: Remove the protector fluid bottle from the hose fitting at the inlet.

Pressure Washer Pump: Lifespan, Replacement, and Care

The longevity of pressure washer pumps isn’t limitless. Just like every other piece of machinery in one’s shed or garage, these pressure-providing components wear down after prolonged use and require replacement at some point.

Instead of spending money on an entirely new pressure washer, replacing the pump can add fresh years to your tool.

• Select the Right Power Washer Pump for a Longer Lifespan with Your Pressure Washer

Choosing an appropriate power washer pump can substantially affect your pressure washer’s lifespan. The accurate pump can extend the overall life of your pressure washer and enhance its performance and efficiency.

Experts suggest understanding your washer’s specifications before proceeding with the purchase to ensure compatibility and optimized performance of the washer.

• Specialty Store: Power Equipment Direct

Power Equipment Direct, a notable online store dedicated to power equipment and accessories, features a host of pressure washer pumps suitable for various models to make buying a replacement pump easier. They offer the convenience of both local pickup and shipping.

• Convenient Pickup Options

Power Equipment Direct lets you choose your desired pickup location to accommodate customer needs best. You can alter the pickup location if required, offering maximum convenience.

Keep in mind that certain restrictions apply. Not all items in their inventory are available for local pickup across all locations. Factors of store selection and stock availability may also play crucial roles.

• Shipping Only Items

Some products listed on the Power Equipment Direct website are designated as shipping only, meaning they are unavailable for local pickup. It’s crucial to check individual product listings for shipping and pickup details to avoid inconvenience.

Understanding the differences between axial and triplex pumps is crucial. Axial pumps are best for light-duty tasks, while triplex pumps, being more durable, are suitable for heavy-duty tasks

• Payment Flexibility

Power Equipment Direct prioritizes the ease of transaction for its customers. They accept myriad payment methods for local pickup orders.

Payment can be made using credit/debit cards, digital wallet services like Apple Pay and Google Pay, and secure online payment systems like PayPal. For high-priced items, they also offer financing options for more manageable payment.

• Complimentary Shipping and Shipping Options

Power Equipment Direct makes the deal even more appealing by offering complimentary shipping on certain products. Note that accessories might be shipped separately based on their size and type.

For more oversized items, they utilize semi-truck shipping, with an additional option for lift gate service to ensure safe transportation of your product to your desired location.

• Surcharges for Remote Areas

While free shipping is an attractive feature, it’s essential to remember that surcharges may potentially apply to remote locations. Before finalizing your order, make sure to check your location.

• Side Note for Better Understanding Pressure Washer Pumps

The Department of Energy’s website provides comprehensive educational material about how pressure systems work. This resource might offer you valuable insights regarding picking the right pump for your washer and also aid you in maintaining the longevity of the pressure washer pump.

• Remarks

A pressure washer pump is a crucial component of your power washer; maintaining it properly can significantly extend the lifespan of your equipment.

Choosing the right pump, ensuring regular maintenance, and resorting to quality service providers like Power Equipment Direct can substantially contribute to your pressure washer’s efficient and smooth functioning.

The Role of High-Pressure Water Pumps in Pressure Washers

Pressure washers have revolutionized cleaning by introducing a more efficient and faster way of removing grime and dirt.

Central to this efficient cleaning system are the high-pressure water pumps. The water pumps propel water at high speed, providing the cleaning force necessary to dislodge dirt and grime from surfaces.

• Understanding the Specifications: GPM and PSI

Primarily, pressure washers function within varying ranges in terms of Pounds per Square Inch (PSI) and gallons per minute (GPM). Typically, pressure washers operate anywhere between 2 and 10 gpm and 500 to 5000 psi. The choice of a pressure washer within this range often depends on the specific need and application.

• Power Source Options for Pressure Washers

One of the highlights of pressure washers is the variety of power sources that can drive them, from traditional sources like gasoline and diesel to renewable ones like hydraulic and pneumatic motors.

They can also draw power from natural gas, electric motors, and power take-offs (PTO). This flexibility makes pressure washers adaptable to various conditions and requirements.

• Catering to Varying Drive Types: Cat Pumps

When it comes to accommodating diverse drive types, Cat Pumps stands out. With an impressive range of pump variations, there is a Cat Pump for each drive type, ensuring seamless operation regardless of the power source.

• The Importance of Quality Pumps for Pressure Washers

Having a quality pump is not just important; it is vital for any pressure washer. It determines both the performance and reliability of the pressure washer.

From my experience, I recommend servicing the pressure washer pump every three months or after 500 hours of use, whichever comes first. Regular servicing can significantly extend the life of your pump.

• Trusting in Reliability: Cat Pumps

Cat Pumps are the industry standard when we speak of reliability and durability. Known globally for their lasting service, Cat Pumps delivers peerless performance for pressure washing, enhancing productivity and profitability.

• Peek into Commercial Applications of Pressure Washers

Pressure washers are incredibly versatile, appearing in a multitude of industries. These range from simple cleaning and sanitation tasks to more specific roles in construction, fleet washing, graffiti removal, and outdoor cleaning.

• Tailored to Meet Your Needs: Cat Pumps’ Product Range

To cater to the different applications of pressure washing, Cat Pumps have a variety of products on offer. Examples include the 4DNX Series, 66DX Series, 5CP Series, high-pressure shut-off gun, and pressure-sensitive unloader.

This diverse offering allows you to choose a product that exactly fits the needs of your application.

• Leveraging Cat Pumps’ Resources

When you choose Cat Pumps, you’re not just buying a pressure washer. You’re also getting access to a wealth of product literature and a high-pressure system design guide. This information helps you make informed decisions and maximizes the return on your investment.

• Cat Pumps: A Testament to Reliable Service

With Cat Pumps, you’re investing in a globally recognized brand that is trusted for its reliability. Its proven record of dependability is reason enough to choose Cat Pumps for your pressure washing needs.

– Conclusion:

Whether you’re running a cleaning business or a DIY enthusiast, choosing the right pressure washer is critical, and it often starts with selecting the right pump.

If you want a reliable and durable pump, the University of Delaware’s Cooperative Extension highly recommends the Cat Pumps. Not only do they offer high-quality pumps, but they also provide resources that guide you on the usage and maintenance of their products.

Water Cannons Discount Incentives on Top Brand Pressure Washer Pumps

Water Cannon, a trustworthy leader in pressure washer products, offers volume discount incentives on various top-brand pressure washer pumps.

These include esteemed brands such as Cat Pump, General Pump, Annovi Reverberi, Comet, Hypro, and Legacy Pump. Recognized for their durability and performance, these brands are favorites among users.

• Role of Pressure Washer Pumps

Pressure washer pumps are crucial in propelling high-pressure water spray for cleaning surfaces.

Using traditional methods, they effortlessly clean surfaces that are otherwise tiresome or near impossible to scrub. Pressure washing is not only efficient and time-saving, but it also ensures a deeper level of cleanliness.

• Affordable Axial Pumps at Water Cannon

At Water Cannon, affordability meets quality. A dedicated category for axial pumps priced under $170 ensures homeowners can avail themselves of this cleaning solution without compromising their budget.

Essential for domestic cleaning tasks, these budget-friendly pumps can handle many pressure washing needs.

• Varied Driving Mechanisms of Pressure Washer Pumps

The mechanical driving force of pressure washer pumps comes in many forms.

These include belts and pulleys, direct drive couplers, gear reduction boxes, PTO geared multipliers, flex couplers, flanges, clutches, poly-drive belt systems, and simple direct drive hollow shaft versions. Such diverse options ensure a match for every unique requirement and use-case scenario.

• A Full Line of Pressure Washer Pump Parts at Water Cannon

Water Cannon maintains a comprehensive line of pressure washer pump parts, including coveted brands like Cat Pump, General Pump, Annovi Reverberi, Comet, Hypro, and Legacy pumps.

This assures users of the seamless availability of parts for their specific pump models. Keeping the maintenance needs of users in mind, Water Cannon makes it simple to source and replace individual components.

• Volume Discount Prices and Free Home Delivery

Water Cannon provides volume discount prices for customers and offers free delivery on orders over $39 for online purchases. This feature offers customers an added convenience and savings, promoting an enhanced online shopping experience.

• Importance of Regular Maintenance

Regular pressure washer pump maintenance ensures a longer lifespan and better, efficient cleaning outcomes. It’s recommended that users regularly replace worn or damaged parts and engage in proactive, preventative care to guard against unforeseen equipment failures.

The National Institute of Standards and Technology (NIST) recommends a regular maintenance schedule for any mechanical equipment, including pressure washer pumps. You can learn more about general equipment maintenance on their site here.

The availability of pressure washer pumps across various prices and brands at Water Cannon makes it a suitable shopping destination. Whether you’re a homeowner, professional cleaner, or business owner, investing in a high-pressure washer pump will pay dividends.

  1. Jim Mccoy says:

    I’ll make sure to perform regular maintenance on my pressure washer pump after reading this article.

    • Allard Vdhooft says:

      Thank you, Jim! Regular maintenance is key to ensuring your pressure washer pump lasts. Let me know if you have any questions. Happy cleaning!

  2. Hilda Jones says:

    How do I prevent water overheating in my pressure washer pump?

    • Allard Vdhooft says:

      To prevent overheating in a pressure washer pump, ensure adequate water supply, clean filters, and replace worn O-rings. Use a pump protector for long-term storage. Regular maintenance is key.

  3. Cassandra Howell says:

    What are the signs that indicate a faulty pump in a pressure washer?

    • Allard Vdhooft says:

      Hi Cassandra, signs of a faulty pressure washer pump include leaks, pulsating output pressure, and low pressure. Check for worn seals, dirty filters, or damaged O-rings for troubleshooting. Hope this helps!

  4. Letitia Bradley says:

    The information provided about the various types of driving mechanisms for pressure washer pumps was useful.

    • Allard Vdhooft says:

      Thank you Letitia Bradley! I’m glad you found the information on pressure washer pump mechanisms helpful. If you have any more questions, feel free to ask!

  5. Johnny Hudson says:

    Is it necessary to use a pump protector in all weather conditions?

    • Allard Vdhooft says:

      Yes, it is essential to use a pump protector in cold weather conditions and for long-term storage when not in use. This will prevent corrosion and damage to the pump.

  6. Miriam Gilbert says:

    Water Cannon seems like a reliable source for pressure washer pump parts.

    • Allard Vdhooft says:

      Thank you, Miriam! I appreciate your positive feedback on Water Cannon for pressure washer pump parts. It’s great to hear that you find them reliable. Happy cleaning!

  7. Clara Pierce says:

    How do I choose the right pressure washer pump for my needs?

    • Allard Vdhooft says:

      Choosing the right pressure washer pump is crucial. Consider factors like GPM and PSI, and ensure regular maintenance to prolong the lifespan of your pump. Let me know if you need more help.

  8. Dana Howard says:

    What kind of maintenance should I regularly perform on my pressure washer pump?

    • Allard Vdhooft says:

      Regularly check for leaks, pulsating pressure, and low output pressure. Clean or replace seals, check the inlet filter, and inspect O-rings for any issues to maintain your pressure washer pump’s performance.

  9. Andy Jordan says:

    I appreciate the tips on how to use a pump protector for my pressure washer pump.

    • Allard Vdhooft says:

      Thank you for the feedback, Andy. I’m glad you found the tips helpful for your pressure washer pump. Happy cleaning!

  10. Mitchell Hoffman says:

    Great video links provided for further understanding of pressure washer pump maintenance.

    • Allard Vdhooft says:

      Thank you, Mitchell! I’m glad you found the video links helpful for understanding pressure washer pump maintenance. Happy cleaning!

  11. Tracy Cooper says:

    How can I fix a pulsating output pressure issue on my pressure washer?

    • Allard Vdhooft says:

      To fix a pulsating output pressure issue, first, check for a blockage in the pump or the inlet filter. If those are clear, it might be due to a leak in the cylinder head causing the pressure to pulse.

  12. Teresa Crawford says:

    Can I replace the pump on my pressure washer instead of buying a new one?

    • Allard Vdhooft says:

      Yes, you can replace the pump on your pressure washer instead of buying a new one. Make sure to follow the steps in the blog post to diagnose the issue and replace the faulty pump. Happy cleaning!

  13. Carl Watts says:

    Thanks for the detailed information on pressure washer pump maintenance!

    • Allard Vdhooft says:

      Thank you, Carl! I’m glad you found the information helpful for maintaining your pressure washer pump. Happy cleaning!

  14. Lewis Wells says:

    This article has been very informative about pressure washer pump issues and maintenance.

    • Allard Vdhooft says:

      Thank you, Lewis! I’m glad you found the article informative. Remember to monitor your pressure washer pump for these signs to ensure it’s working optimally. Happy cleaning!

  15. Francis Campbell says:

    How can I avoid damaging my pressure washer pump due to overheating?

    • Allard Vdhooft says:

      Regularly clean filters, replace worn seals, and ensure adequate water supply to prevent pressure washer pump damage. Proper maintenance is key to avoiding overheating and other issues. Happy cleaning!

  16. Frederick James says:

    I didn’t know about the importance of choosing the right power washer pump for my pressure washer.

    • Allard Vdhooft says:

      Thank you for your comment, Frederick! Choosing the right power washer pump is crucial for the longevity of your pressure washer. Make sure to assess your pump regularly to ensure optimal performance.

  17. Pedro Marshall says:

    What are the consequences of cavitation in a pressure washer pump?

    • Allard Vdhooft says:

      Hi Pedro, the consequences of cavitation in a pressure washer pump include noise, vibration, loss of capacity, and potential pump damage. It’s essential to ensure sufficient water supply to prevent cavitation.

  18. Jason Lopez says:

    I had no idea about the volume discount incentives for pressure washer pumps at Water Cannon. Thanks for sharing!

    • Allard Vdhooft says:

      Thank you for your kind words! I’m glad you found the information on volume discount incentives for pressure washer pumps helpful. Happy cleaning!

  19. Edward Mendoza says:

    The explanation on the role of high-pressure water pumps in pressure washers was very insightful.

    • Allard Vdhooft says:

      Thank you, Edward Mendoza! I’m glad you found the information on high-pressure water pumps insightful. If you have any more questions, feel free to reach out. Happy cleaning!

  20. Sherry Hopkins says:

    What is the expected lifespan of a pressure washer pump?

    • Allard Vdhooft says:

      The expected lifespan of a pressure washer pump varies depending on use and maintenance. Factors like leaks, pulsating pressure, and low output indicate pump issues. Regular maintenance ensures longevity.

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