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Sun Joe Pressure Washer troubleshooting: With Helpful tips

Sun Joe pressure washers are among the best-valued budget-friendly electric pressure washers on the market. But even those machines can have a failure. This blog post will help to troubleshoot the most common issues with a Sun Joe pressure washer.

Sun Joe Pressure Washer Troubleshooting:

To troubleshoot your Sun Joe pressure washer, the first step is to identify the type of problem. Is the pressure washer not producing the correct pressure? Is the output pulsing high and low? Is there a motor or pump problem? Or is the pressure washer pump or another part of the machine leaking? Knowing the type of problem, you can use our diagnose table to find the cause and solution.

This article will provide you a complete guide to troubleshoot your Sun Jow pressure washer. It will give you information about the reasons that cause the electric pressure washer not to work correctly and provide solutions to these problems.

Diagnose and troubleshoot a Sun Joe Pressure Washer

Use the following table to diagnose and troubleshoot a Sun Jow pressure washer:

Pressure washer not producing high pressure
Hose with small diameter
Replace your hose with a 1″ (25mm) or 5/8″ (16mm) hose
Restricted water supply to the washer
Check for the kinks and leaks in the hose
Inadequate water supply
Ensure the water source is unobstructed and fully turned on
Clogged intake filter
Remove the filter and rinse it with warm water
Air in the pump
Ensure that the hose and fittings are airtight. Shut off the washer and squeeze the trigger until water flows steadily from the spray tip
Suction tube or detergent bottle not connected properly
Install the suction tube and detergent bottle correctly
Detergent too thick
Dilute the thick detergent by adding water
Obstructed spray tip
Remove the debris with a needle
No pressure tip on the wand
Install a suitable pressure tip at the end of the wand
If your model has a belt, it can be loose.
Tighten or replace the belt.
Motor won’t start
The power switch is in the “OFF” or “0”  state
Turn the power switch “ON” or “1”
Cord not plugged
Plugin the power cord
Damaged, too long, or improper extension cord
Replace the existing cord with a 25′ (7.6m) 14 AWG cord or a 50′ (15m) 12 AWG cord
Inadequate power from the electrical outlet
Plug the cord in a different outlet
The pressure washer circuit breaker tripped
Wait for the washer to cool down and restart it
Noisy Pump
Air in the pump
Ensure that the hose and fittings are airtight. Shut off the washer and squeeze the trigger until water flows steadily from the spray tip
Clogged inlet filter
Remove the filter and rinse it with warm water
Pump leaking water
Damaged or worn water seals
Replace the seals with new ones or call a professional
Loose fittings
Ensure that all the fittings are tight
Leaks in the spray wand, spray tip, or extension
Damaged or broken O-rings or plastic insert
Replace the worn O-rings or call a professional
Pressure washer pump dripping oil
Worn or damaged pump oil seals
Inspect the pump oil seals and replace if worn
No water from the washer outlet
The water supply is off
Turn the water supply ON
Kink in the hose or faucet
Remove any kinks and debris from the hose or water lines
Motor buzzes but fails to run
Loss in voltage due to the extension cord
Plug the unit directly into the outlet without an extension cord. If the problem isn’t solved, replace the extension cord
Low supply voltage
Ensure that only the pressure washer runs on that circuit at the time of use
Residual pressure in the system
Shut off the washer and squeeze the trigger to release pressure
Residual friction among the internal components
Cut the water supply and turn the machine ON for 2 to 3 seconds. Try it a couple of times or until the motor starts. Don’t let the machine run dry for more than 3 seconds.
Unit not used for long periods
Call a professional

Why is my Sun Joe pressure washer pulsating? Some useful tips

Generally, the most common reason for a Sun Joe pressure washer pulsating is a lower water supply, a kink in the hose, or blockage in the inlet filter. Other reasons are air leakage or air trapped in the pump in the machine. A worn-out or clogged nozzle, a problem with the unloader valve. Or another reason why there is less water going through the machines than expected.

The following reasons will help to find the cause of your Sun Jow pressure washer pulsating:

Reason 1: Problem with the water supply, hose, or the inlet filter

The first reason to check if your Sun Joe pressure washer is pulsating is a restricted water flow. This can be a lower amount of water arriving at your pressure washer. Ensure that the faucet is fully open and that the hose running to the pressure washer is fine. When you use a long hose, first try a short thick one. Try to minimize the number of bends. The wider the hose, the more water will arrive.

Check and clean the inlet filter. Over time dirt from your water supply will be collected there and lower the amount of water going to the pump.

Next, check the high-pressure hose. Ensure that there are no kinks or leaks in the hose of your pressure washer.

If you use detergents, some leftovers can build up near the detergent tank and block some of the water. Check and clean the area. If it is hard to remove, use some distilled vinegar.

Reason 2: Nozzle

Another reason for the pulsating pressure can be a worn-out nozzle. If you notice an unusual spray pattern, this is a sign of a worn-out nozzle. Nozzles can wear out after heavy usage, or small particles can partly clog it.

To easiest method to check this is using a replacement nozzle. If you do not have a matching replacement, use another type and see if this solved the pulsating problem. If the pulsating pressure is gone, there is a problem with the nozzle.

If it shows wear and tear, replace it. If the nozzle looks good, check for dirt in the nozzle. Clean it thoroughly using a nozzle cleaner or a thin metal wire.

Reason 3: Pressure pump

If your Sun Joe pressure washer is still pulsating, the pump could be the reason. Sometimes, the air gets trapped in the pump that causes the water pressure to pulsate. You can fix this problem by bleeding the pump.

First, disconnect the garden hose. Let the water run until you only see water, and all the air has gone. Turn off the water, and connect the hose to the pressure washer. Disconnect the high-pressure hose. Turn on the water source and go through the pump for half a minute or so. Turn off the water and connect the high-pressure hose. Try if this fixed the pulsating problem.

Reason 4: Damaged unloader valve

If your electric pressure washer is still producing pulsating pressure, you may have a problem with the unloader valve. The unloader valve diverts the water flow in the pressure washer causing the water to flow back in a loop to the pump. If the unloader valve is not working correctly, the pressure washer can result in the pulsation of the water pressure. To fix this problem, check the springs and seals of the unloader valve. Replace it if it is damaged or try to readjust the unloader screw.

Reason 5: Water leaking from the pump

The pulsation in the outlet pressure of your Sun Joe pressure washer can also occur because of water leaking from the pump. There are two main reasons for this. The first is if the pump casing is not sealed properly. The second is due to the activation of the thermal valve. To seal the casing, ensure that the seals are not broken or worn. Tighten the bolts off the pump assembly. If the water leakage is due to the activation of the thermal valve, turn off the washer and allow it to cool down for few minutes before using it again.

How do I fix my Sun Joe pressure washer? Some useful tips

In general, the first step in fixing a Sun Joe pressure washer is checking the fuse, the power outlet, and the power cable. The next step is to check the inlet filter, unloader valve, and capacitor for any damage or clogs. 

An electric pressure washer contains a lot fewer parts compared with a  gas pressure washer. It requires a lot less maintenance, but it can still fail. Use the following steps to diagnose and fix the most common issues with a Sun Joe pressure washer:

Step 1: Ensure that everything is dry

Before troubleshooting your Sun Joe electric pressure washer, make sure that your hands are completely dry. Water and electricity do not match and are dangerous.

Step 2: Check the cord and AC outlet

If your machine does not do anything, the first step is to check the power cord for any wear and tear. Make sure that all the connections look fine. Also, ensure that the AC outlet is providing enough voltage to operate the machine. Check it with another appliance, like a lamp. Also, check if the extension cable is fine if you use that.

If there is a problem, check the fuse in the house. It is also possible that the earth leakage circuit breaker has tripped because of moisture. Even when all is fine, it is always a good idea to check an other wall socket.

Step 3: Check the fuse

The next step is to remove the fuse from the pressure washer and check it. Use a multimeter to check it. Place the probes of the multimeter at each end of the fuse, use the resistance setting. Check what the multimeter shows. A perfect fuse has approximately zero resistance. If you do not get a very low number, it means the fuse is broken. You need to replace it with a new one.

Step 4: Examine the capacitor

To check the motor capacitor, remove the case that covers the motor. Find the capacitor. A blacked capacitor indicates that it is burned. Disconnect the burned capacitor’s legs from the wires of the motor, and install a new one. If you are unsure how to do this, ask a professional for help.

Step 5: Check the water supply

Ensure that your water source can supply the needed pressure (PSI) and amount of water (GPM). If the pressure is not high enough, it can lead to air bubbles (cavitation). And cavitation can lead to pump damage. If the water source does not supply enough water, it can result in a pulsating pressure.

Check the minimum pressure for your Sun Joe model in the manual. I have to add that my experience is that a slightly lower pressure will still work fine. You can check the water pressure with a pressure gauge. And the amount of water by filling a bucket with the hose. Measure the time it takes with a stopwatch. And use that to calculate the Gallons per Minute (GPM).

Step 6: Check the unloader valve

If your Sun Joe electric pressure washer produces no pressure, you may have a problem with the unloader valve. The unloader valve diverts the water flow in the pressure washer to flow back in a loop to the pump when the trigger is not pressed. If the unloader valve gets damaged, the pressure washer produces low pressure or no pressure at all in some cases. To fix this problem, check the springs and seals of the unloader valve and replace it if it’s damaged or try to readjust the unloader screw.

● Step 7: Faulty Pump

Sometimes electric pressure washers produce a pulsating pressure. This means that the pressure frequently changes between high and low. There can be a problem with the unloader valve. But if you have checked it and it is fine. There can also be a problem with a damaged inlet, manifold, or pump valve that causes a pulsing pressure. To solve this problem, take out the pump from the washer and clean its components.