10 Reasons Pressure Washer Pumps Fail


Pressure washers are great tools. However, sometimes their parts begin to break down. One of the most commonly broken parts is the pressure washer pump.

1. Dirt in the Pump

Pressure washer experts have found that 9 out 10 times, if a pressure washer has low pressure, the low pressure is caused by dirt in the pump. The dirt causes blockage in the hose, lance, or nozzle. Simply replace the nozzle, and the pressure level will rise. If you do not want to replace the nozzle, or recently have replaced it, it is possible to clean the pressure washer pump.

How to Clean Pressure Washer Pump

Step #1 Switch Off the Power Washer.

Step #2 Take Out the Pressure Pump from its Bay.

Step #3 Give the Pump Water Treatment.

Step #4 Run the Power Washer.

2. Pump Cavitation and Overheating

Two other things that can cause a breakdown of a pressure washer pump are pump cavitation and overheating due to excessive time in by-pass. Pump cavitation is caused when there is not enough water supplied to the pump. The supply of water to your machine must be higher in gallons per minute than the rating on the pump. If your washer is older and not giving you the level of service that you expect, then it is probably time to arrange for some repairs to your pressure washer, or replace some of the worn-out parts.

3. Pump is Worn Out

Most low cost pressure washers are made with lower quality pumps. The life expectancy of these pumps is around 60 to 100 hours of use. With higher quality pressure washers, the life expectancy of their pumps is closer to 500 hours, although the higher quality pressure washers are mainly made for people who use the pressure washers while working. On average, households use their water pressure washer around 50 hours per year. If you are worried that your pressure washer pump is becoming worn out, you can take it to be looked at by an expert, and they can tell you if something is wrong with your pressure washer, or if the pump is becoming worn out.

4. Leaking 

The pressure washer pump can begin to leak, or not work as well as it usually does because of a leak somewhere in the pressure washer. There are numerous seals that are distributed throughout the design of the pressure washer and any one of them may fail spontaneously to create a leak. It isn’t just water that can leak either. Oil leaks are also very common. Make sure that you check your seals at least twice per year and quickly replace ones that appear to be worn out.

5. Pulsating

A pulsating pressure washer is not necessarily caused by a damaged or worn out pump, but it can cause damage to the pump. This issue is almost always caused because of a dirty inlet or discharge valve. Make sure that you clean these out thoroughly after 5 or 6 uses, especially if you are pressure washing wooden materials. Even hardwood will splinter at times when high-pressure water streams are encountered. These small splinters then clog up the system. You may also have a stuck plunger for a wide variety of reasons. If your inlet and discharge valves are clean, then the plunger is the likely cause of the pulsating, especially if you have low pressure while this is happening.

6. Incorrect Nozzle

An incorrect nozzle or a nozzle that has worn out can cause the pressure washer pump to wear out faster or cause it to fail. Make sure that there is water coming to the equipment properly as well – a hose that is going up a hill will delay water pressure from arriving, and extended use of a pressure washer with the hose going up a hill can cause the pump to fail earlier than expected since it has to work harder than usual and work against gravity. You will need to replace any worn out or broken nozzles when they are discovered.

7. Worn-out Plunger

You may have a plunger that has become worn out or broken, or the belt on your pressure washer may be slipping. This can cause the pump to wear out or fail faster than expected. The repair of the plunger and belt can both be done at home with the proper spare parts, but you may need to order them directly because they are often model specific. If you do not feel comfortable fixing the pressure washer yourself, it is relatively easy to find someone who you can pay to repair it.

8. Loose Fittings or Stuck Valves

If the fittings have become loosened by use, or the valves have become stuck because of hard water deposits left when the water evaporates, the pressure washer pump can begin to fail.

9. Lack of Oil

Catastrophe failures of the pressure washer pump can be caused by low or no oil in the pressure washer. If this happens, you will be required to replace the pressure washer pump. Make sure to check the oil level in your pressure washer before you use it so you can avoid this. It is a simple task that will prevent a large expense.

10. Water

Pressure washer pumps can fail if they have been stored with water still in the pressure washer. This happens because the water can freeze and crack the housing of the pump. The waster can also cause internal corrosion.

Is It time for a New Power Washer?

With a little proactive maintenance and some tender loving care, a vast majority of pressure washers from today’s top manufacturers will give you a long lasting tool that you can use to effectively clean all of your property. A professional can help you find and choose the pressure washer that best meets your needs. It is sometimes more financially reasonable to replace your unit than fix it. Either way, a professional pressure washer maintenance person can diagnose the problem and give you options. If you want to pay someone to fix your pressure washer, the average cost of a power washing service is $283, with a typical range of $185-$383. 

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