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Can You Fix a Pressure Washer Pump? Tips From Professionals

Pressure washers allow you to effectively clean your car, patio, driveway, and other outdoor areas of your house. They are reliable machines, but wear and tear can affect the performance of your pressure washer over time. Problems can occur with the gas engine or the pressure washer pump. This pump is the heart of the system and is responsible for creating high-pressure water.

How to Repair a Pressure Washer Pump:

You can fix a damaged pressure washer pump. A lot of issues are due to worn-out seals, O-rings, the piston, or loose-fitting of the pump. These components of the pump can be replaced or repaired. Depending on the brand, you can purchase a valve kit, plunger/piston kit, a high-pressure seal kit, or an oil seal kit. In case of a serious malfunction, you may need to replace the whole pump.

This article will provide you how to diagnose the faults in your pressure washer pump. And how to repair your faulty pump.

How to Diagnose a Faulty Pressure Washer Pump, some helpful tips:

Several indicators indicate a faulty pump. These are leaks, pulsating, and low output pressure. This section will provide you with information to easily diagnose the fault in the pressure washer pump and fix it.

● Pressure Washer Pump Leaks

Leaks are one of the most common problems with pressure washer pumps. Leaks are caused due to damaged or worn seals or other faulty components. A leaking hose indicates a worn O-ring or gasket, which you can replace. A leak from the cylinder head or inlet/outlet elbow is due to water inside the pump not being completely drained. If this water freezes in winter, it will expand and damage the plastic parts of the pump.

To identify the leaks, remove the case of the pressure washer and turn the water on. Please don’t turn on the machine with its case is removed yet. Water coming from the hose will run through the pump and indicate the area from which the leak is originating. If that doesn’t show anything, you can try it with the machine on.

● Pressure Washer Pump Pulses

The main reason that causes the motor to pulse or restart is an insufficient water supply in the inlet. You can remove the filter on the inlet and clean the blockage to supply sufficient water to the pump. A leak from the cylinder head can also lead the motor to restart or pulse.

● Pressure Washer Pump Low pressure

Low pressure is due to a damaged O-ring. This is a rubber gasket that seals the inside of the pistons and valve. This problem can be fixed by replacing the worn O-ring. However, if the seal is fine, then low pressure can be a result of dirt blockage. To restore the machine’s pressure, clean the filters and remove all dirt and debris that are preventing the adequate supply of water to the pump.

Pressure Washer Pump Repair Guide, with helpful table:

Many pressure washer problems are the result of a pump issue. These are problems related to water pressure, excessive noise, oil, and water leakage. They are often the result of damaged seals, gaskets, and other pump components. The table below shows the most common problems, what causes them, and how to fix them:

How to fix
No pressure
Damaged inlet valve
Disassemble the pump and clean the inlet valve. If the problem still occurs, replace the inlet valve.
Damaged unloader valve
Adjust the unloader screw. Also, check for damaged seals and springs.
Inconsistent pressure
Damaged inlet valve
Sometimes there is pulsing pressure from the outlet, which means that pressure fluctuates high and low constantly. This can be fixed by cleaning or replacing the inlet valve.
Faulty pump
Replace the pump.
  Air sucking pump
Turn off the washer and release the pressure inside the pump by squeezing the trigger gun.
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 from the pump
Damaged seals, gaskets, or pistons
Disassemble the pump and check the seals or pistons. If they are worn or damaged, replace them.
This can be due to loose bolts and the fitting of the pump assembly. Check the pump assembly and tighten it if it is loose.
Low pressure
Insufficient water supply
Ensure an adequate water supply to the washer by unkinking the hose or using a hose with a large diameter (3/4 “recommended).
Inlet filter 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.

Pressure Washer Pump Repair tips:

The most important part of the pressure washer is its pump. The pump sucks the water from the faucet and squirts it out through a high-pressure jet. The pump gets damaged due to an insufficient water supply, worn-out seals, and several other reasons. Here are some tips that can help you while repairing your pressure washer pump.

● Tip 1: Check the oil

Look for the sight glass at the side of your pressure washer. Sight glass shows the level of the oil in the machine. If the oil level is below the recommended point, add oil to the pump. Some cheaper models have a closed-loop system. Oil is added during manufacturing and can not be replaced or added.

● Tip 2: Siphon out the cloudy oil

When water gets mixed with the oil, it gets cloudy. First, you must remove the cloudy oil with a siphon to prevent it from damaging the pump. Then, replace the old oil with fresh oil.

● Tip 3: Prime the pressure washer

If the pressure washer’s pump doesn’t provide a good flow, you can prime on the input side of the pressure washer. You can use a prime kit for this. Such a kit will ease the pressure in the line enabling you to start a gas engine more efficiently. It will also release the air from the high-pressure side of the pump. As soon as air and a little water have been ejected from the easy prime valve, you can close it. The high-pressure hose and lance will be ready, and there is no need to hold the trigger open as the pump primes.

● Tip 4: Allow the air to escape

Unscrew the hose from the pressure washer and allow the air to escape from the pump. Then attach the hose again and restart the pressure washer to get compression in the pump.

● Tip 5: Clean the chemical strainer or filter

A chemical strainer or filter produces noise when the pump gets clogged. If you are using a chemical strainer, disconnect the hose from the strainer. Next, clean the strainer with water and a small brush after opening it from the bottom. Once it’s cleaned, reattach the strainer with the hose and turn on the washer. If your pressure washer still isn’t working correctly, then it’s time to replace the pump.

● Tip 6: Check the seals and the O-rings

If the seals and the O-rings of your pressure washer are worn, the pump won’t work correctly because the air will escape. Service dealers possess the specialized tools to replace the seals and O-rings; therefore, you should take your pressure washer to the service dealer to have the seals checked.

Repairing a pump damaged by dirty or insufficient water, some helpful tips:

Here is a simple guide to fix a pump that is damaged due to dirty or insufficient water:

● Step 1: Turn off the pump

Turn off the pump and before starting the fix.

● Step 2: Check the filter screens

Check the intake valve and filter screens. The filters get clogged with dirt and other matter, which reduces the flow of water. A pump may get burnt if the flow of the water to the intake valve decreases below a certain value.

● Step 3: Clean the filter screens

Clean the intake valve and filters. If they look really bad, replace them.

How to fix the low level of oil in the pump, some helpful tips:

The pump will get hot and eventually even may stop working if the oil level is too low. Check the pump oil level through sight glass on the side of the pressure washer. If the oil level low, fill the pump oil according to the manual.

How to repair a pressure washer pump leaking oil, some helpful tips:

Broken or worn-out seals are one of the more common pressure washer pump issues. Seals can break due to poor maintenance. Or because they are old and have seen a lot of contraction and expansion. Humidity causes the seals to contract and expand. Broken or worn-out seals cause oil and water leakage. Fixing a pressure washer pump that is leaking oil is not as difficult as you think. Use the following steps:

● Step 1: Buy an oil seal kit

Generally, oil seals are made of rubber and can be replaced on most more expensive pressure washer models. If your pump is leaking oil, purchase an oil seal kit that best fits your particular pressure washer model. Oil seal kits will differ from brand to brand and can vary from model to model. The oil seal kit should contain various rings and seals.

● Step 2: Change worn-out or broken seals

Disassemble the pump and replace the rings and seals. Always replace all of them. Assemble the pump and check if the issue has been solved.

How to repair a cracked pressure washer pump, some helpful tips:

A pressure washer pump gets cracked if the water left inside the pump freezes. Frozen water will expand and damage the pump seals. The forces are so great that they can even damage the pump housing. And in severe cases, the pump may break open.

Here are some of the steps that you must follow while dealing with the cracked pressure washer pump:

● Step 1: Inspect the pump

The first step is to look for the crack in the pump. This will give you an idea of the condition of the pump and guide you further.

● Step 2: Brazing or JB Weld

For an immediate remedy, you can weld or braze the crack. However, keep in mind that these methods are not 100% reliable and often don’t completely fix the problem. Also, a pressure higher than 2000 PSI is serious pressure, and welding isn’t advisable. If you have a pressure washer with a high PSI rating, I always recommend replacing the pump.

● Step 3: For bigger cracks, replace the pressure washer pump

If the crack is big enough, then the replacement of the pump is the only option. Look for pump assembly parts on Amazon or at your local dealer. Ensure that you buy the new part according to the make and model of your pressure washer.