Your fun cleaning day with a pressure washer can be ruined if the pressure washer starts to pulsate. You may have strong bursts of high pressure followed by pauses of low pressure. It makes your job wearisome, take more time to get it done with and you end up using a lot more water. To make sure you have an efficient and fun pressure washing experience and avoid frustration, you need to troubleshoot a few issues to get a constant flow rate of water pressure that pushes away grime and dirt.
Table of Contents
Pulsating pressure usually requires an easy and quick fix but it can also be a sign of a larger problem. Therefore, it is important that you approach the problem with cautions and try to fix it as soon as you feel there is something wrong with the pressure washer. If your pressure washer is pulsating, it can be prevented with various easy care tips.
Leaks and blockages in the discharge valves is the most common cause of pulsating in pressure washers. An unloader valve is that part of the power washer that lets the pump to bypass the water flow back to the pump when you are not using the spray gun. The rapid opening and closing of the dirty inlet or discharge valve in the pump can cause the pulsation while using a pressure washer. The unloader valve can go into a bypass mode due to enough obstruction downstream from the pump. It pulsates because the restriction is only slight that puts the unloader valve into bypass for a short bit, then goes back to produce high pressure output in a rapid succession. This causes the pulsation felt.
The restriction is most likely to come in the small orifice of the unloader valve at the end of the wand. The opening is usually smaller than a millimeter, and can be clogged with a tiny obstacle. Consult the owners’ manual of your model and look for the process to clear the obstruction. This problem can usually be fixed by clearing the obstruction with a small wire, removing the nozzle, or black flushing the wand and unloader valve. Inspect valves to ensure the garden hose inlet screen is not missing or torn to ensure proper water flow. Also, check the pressure regulator that comes on the most unloader valves for the desired output pressure of the pump.
Before using, make sure that the hose does not have any leaks or kinks as it can mess the pressure and can damage the machine. Also, hard or dirty water can block the little divots which need to be regularly cleaned to avoid pulsating problems. Be aware that detergent oil suction can also cause pressure problems to your pressure washer as the oil builds up in the nozzles. Therefore, you are recommended to use non-detergent oil. To clean the detergent oil build-up, run distilled vinegar through the detergent suction to clean the clogged debris and dirt.
Pressure Washer Pump Failure
Pressure washer pump failure may sound like a disaster, but it doesn’t mean it can’t be repaired. If pulsating continues after you have cleared the unloader valve of clogs and blockages, you might want to have a look at the pump.
The pump can trap some air that needs to be fixed quickly. To fix the pump, disconnect the high-pressure hose after turning off the pressure washer while keeping the garden hose connected and let water run through for a minute. Turn off the garden hose and reassemble the unit. Test the pressure washer by running it normally and see if the problem is fixed. Additionally, check out these amazing pressure washers for house cleaning.
To ensure your pressure washer unit is working properly, the pump needs to be in a perfect condition. Also, be mindful that if an adequate water supply doesn’t go in the pressure washer, it can cause low pressure. Some models require the inlet water supply at full force. Make sure a proper supply of water to the pump. Keep the garden hose turned completely to let more water into the pump for good water pressure.
Trigger Issues
When pulling the trigger gun of your pressure washer doesn’t have the desired effect, you need to stand there and think about the possible underlying causes of it. Firstly, you might find it a no brainer, but think about the last time you refilled the oil or fuel in your washer. You can make this common mistake if you do not use your pressure washer regularly [1]. Low or dirty fuel or oil can affect the performance of the unit. You might want to check the levels of pump oil and make sure it has fuel and the spark plug is connected properly to the wire before putting the power washer to work to get satisfactory water flow.
Secondly, pressure washers, especially the electric pressure washers, can overheat. It can happen if you are using it for too long or if you are working in hot weather. The longer you use it, the more heated the system will be. Hot or humid weather can make it a lot worse. If this is the case, try turning the unit off for about half an hour and try again. Moreover, discover this awesome guide about the pressure wash a pool and spa.
If the pressure washer shuts off on releasing the trigger, it has some problem with the unloading valve that stalls the engine pump. The unloader valve is the most neglected part of the pressure washer and this is the area which can cause that sudden shut off. It plays a crucial role in the machine’s performance. It makes the pressurized water recirculation to prevent it from damaging the pump. If it gets clogged, it can decrease the pressure drastically.
Clogged Nozzle
A clogged nozzle will not give you the same level of job satisfaction. The dirty water inlet hose can cause pressure washer pulsating. Clean the nozzles regularly to limit clogs. For most models, you can simply disconnect the spray wand and push out clogs with a wire and flush it with water to clear off debris.
Nozzles get clogged over time, with prolonged use. If you use the pressure washer a lot, the wear and tear will be faster as well which results in problems for your unit. Dirty water or worn out materials can build up within the nozzle to cause caking. Moreover, detergents can cause corrosion or erosion if not washed out properly. To correct a surging pressure washer remove the nozzle and clean it with the cleaning kit and attach it back again. Furthermore, check out this amazing guide about presser washer nozzles.
You can prevent this problem by changing nozzles according to your need and the requirement of the job at hand and the surface you are working on. Pressure washer surging can also be caused due to a partially plugged spray nozzle, so make sure to check that.
There are numerous parts and tools with which you can maintain and clean your unit regularly. Usually, every model comes with its own nozzle cleaning kit, but it is better to be prepared with other tools that can help you solve problems like clogs and other similar small scale issues.
Water Temperature
If you are using a cold water machine, make sure you don’t have a hot water supply with greater temperature than 140°F running through it as it can damage the pump. To avoid serious defects to your washer, make sure you use hot water pressure washers that are specifically designed for hot water, if you want to use hot water for cleaning.
Hose and Air Filters
Pulsating pressure washer can be corrected by cleaning the air filter or replacing it if damaged. The unit may lack power run water or the engine fails to start until all air is removed from the hose. Make sure to check both hose and air filters are in good shape before using the pressure washer to ensure the best pressure washing experience.
Internal Pressure Built up
Pulsating pressure washer can be caused due to built up internal pressure which trips the bypass valve. When the pressure is relieved, the cycle starts all over again. To solve this issue, see if the pump has hex-head caps on the tops of every piston bore. If it does, take off the caps and carefully pull out the spring-loaded valves that are located just under the caps. These one-way valves will be situated against the pump body with an O-ring but they can be taken out easily. Check valves and compare them. You will find a light spring inside the plastic cage that holds a dish-shaped metal valve at the bottom of the valve. You may find small pieces of rust or grit that is pulling the valves off of its seat. Clear that grit and rust and reassemble the pieces and check if the pressure washers work properly.
Tools you Must Have for Pressure Wash Maintenance
There are several simple and easy to use tools that help you keep your pressure washer in its best condition. These tools are:
Nozzle Cleaner Wire
Hose Extension
Pump Saver
O-Ring Kit For Pressure Washer Pumps
Cleaner Wire
A wire with which you can clean out tiny crevices is the easiest to get. You can use anything from the wire of a twist tie to a stretched-out paper clip or you can innovate with anything. But, it can be frustrating to find a tiny thing like these when you need a solution right away and clean the nozzles as soon as possible. Keep a dedicated cleaner wire in your toolbox to alleviate that frustration and help with quick fixes as you need them.
Hose Extension
You might think hose extension is unnecessary but you will be surprised to find that such a thing can protect your machine by allowing you to move it to the areas you want to reach. Moving your pressure washer around increases the risk of damage. A good quality hose extension saves you from having to pull the unit around while cleaning which is a lot of work.
Pump Saver
A heavy-duty pump saver can be your saving grace. It supports the piston of the pressure washer. A pump saver is a must when you want to store your pressure washer for a long time. Additionally, check out these amazing ultrasonic cleaners for suppressors.
O-Rings Kit For Pressure Washer Pumps
O-rings are the small rubber circles in the nozzle of the pressure washer. They need replacement from time to time as they wear and tear over time. Replacing them at the right time will save you from the nozzle hassle later. Worn out rings can make the nozzle prone to get damaged. Keep the nozzles clean, sealed and protected with a stash of rings around your workspace.
Kenneth Cutler is the founder and head editor at Clean My World. Based in California, he has been writing about home cleaning and cleaning appliances for quite some time and various major brands such as Miss Mill Mag and Lifestyle Magazine. Over the years, Kenneth Cutler has reviewed thousands of vacuum cleaners and other related home appliances and products. This enabled him to develop a unique insight into what makes a good vacuum cleaner. He keeps an eye on the market trends and USA regulations. Apart from talking about cleaning stuff, he likes to play music and enjoys live concerts.
