Why does my Pressure Washer Leak Water or Oil – Quick Fix

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The tedious job of washing cars at home has become quite convenient with the help of pressure washers. You get the same results as a professional car wash without going out and spending loads of money every time. Not just cars, you can use a pressure washer to wipe any surface clean. However, as handy as a pressure washer is, it can be a source of a nuisance when the machine leaks water or oil in your garage.

Why Does My Pressure Washer Leak Water Or Oil

Leakage in your pressure washer causes hindrance during the job. It also leads to the machine getting damaged and your money being wasted. To save you from the extra fatigue of taking the machine to the maintenance store, we have listed some ways you can identify the leak in your machine. This article is going to help you fix your machine at home without spending any extra bucks on the repair.

Reasons Behind Leakage

If you find water and oil stains beneath your pressure washer, do not panic. Your machine is not completely broken. With a little tinkering, it can be as good as new. There are many reasons behind a leakage in a pressure washer; the major reasons are discussed below.

Overfilling The Pump

Leakage does not always mean a broken machine. Sometimes there is leakage when you overfill the pump of your pressure washer with oil. When the machine has been overfilled then obviously it is going to leak water and oil. Before jumping to any conclusions, check if your pressure washer has been overfilled or not.

Broken Piston Pump Seals

If over-filling is not the case, then you are definitely dealing with a broken seal. Pressure washers come with multiple seals added to the piston pump. As pressure washers are heavily used for a longer duration, it is only natural that one or two of the seals break down, resulting in a leakage.

If the oil leakage is foamy, then a seal on the inside of the pump has been broken. On the other hand, if the leakage happens at the pressure washer’s seams, you are dealing with a blown seal on the outside. Check the type of leakage closely so that it is easier for you to repair your machine.

Worn Out Plunger Pump Seals

If your pressure washer does not have a piston pump, then the reason behind the leakage of oil in your machine is a worn-out and broken plunger. Heavy users of pressure washers mainly face this problem. The plunger pump seals are constructed from ceramics. They get damaged when the machine is used heavily and is not taken care of properly.


This reason is not the major cause behind a leakage in pressure washers, but it is still a factor that plays some role in leakage, so we can’t overlook it. If you live in an area with highly humid weather, then the seals on your pressure washer will expand and get damaged due to the temperature, hence causing a leakage.

How To Fix The Leakage

Now that you have identified the type of leakage under your pressure washer, it is time to deal with it. With the below-stated ways, you will be able to fix and repair the broken seals of your pressure washer in no time and will have a machine as good as new.

Get An Oil Seal Kit

Before you purchase an oil seal kit, you need to know the type of your pump and whether it is a piston pump or a plunger pump. Once you know the type, get your hands on an oil seal kit that matches with the one on your machine. If your machine is leaking water, then get a water seal kit too.

Replace The Broken Seals

Disassemble the pump carefully. Make sure to put all the nuts and bolts of each part close to them so that reassembling does not give you a headache. Once the entire pump has been disassembled, locate the defective seals and replace them with the new one from the oil seal kit. Put all the parts back in their place carefully, and refill the pump with fresh oil.

How To Avoid Leakage

It is extremely annoying to discover that the machine you spent hundreds of bucks on is leaking oil and leaving behind stains all over your garage. However, it is not a problem that can’t be dealt with. There are a few ways through which you can avoid oil or water leakage in your pressure washer.

Avoid Overfilling The Pump

This is not rocket science. When you overfill your pressure washer’s pump, then expect half a liter to be leaked and spilled under the machine. If you do not want to spend hours scrubbing the oil stains off your garage floor, then avoid overfilling the pump.

Replace Seals Yearly

This reason is a must for the people who are heavy users of pressure washers. If you spend half of your day using your pressure washer, then you need to keep checking the seals and change them seasonally. Changing the seals yearly will ensure that your machine does not leak oil or water. This will prolong its life and ensure that you don’t end up with stubborn stains in your garage every season.

Avoid Usage In Extreme Weathers

One last tip that will help you keep the oil leakage in control is not using your pressure washer in extreme weather conditions. As we know, highly humid weather is one reason behind leakage; try to avoid taking your pressure washer out on hot summer days.

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A pressure washer is quite a handy tool that lets you wipe any surface clean in no time, without you wasting any extra energy. However, if you do not take care of your machine, the situation will be the other way around, and you will be stuck with a machine that will merely be a source of annoyance for you. I hope this article helped you find out why your pressure washer is leaking water or oil and how you can deal with it.


1. Why is my pressure washer leaking water underneath?

The transparent adapter is not correctly placed, which causes water to leak from the adapter connected to the water inlet. The threads allow water to leak into the unit's case, and it spills out of the bottom.

2. What is the most common problem with pressure washers?

Many pressure issues begin and end at the unloader. Typically, a broken o-ring, a clogged spring, or a blocked shaft can be repaired by removing the unloader and inspecting it for damage.

3. Why does my pressure washer keep losing pressure?

There may be a reduction in pressure due to worn packing or significant cavitation (bubbles) in the fluid you are pumping. Occasionally, this condition can occur due to a lack of water or insufficient filtering. To fix it, you'll need to install a suitable filter.

4. How long can you run a pressure washer?

The machine can continue to run for as long as it has. When you're finished using the machine, turn it off and separate the power hose from it to relieve the pressure in the hose. Water should be pouring out of the quick-connect where the power hose connects at this point.

5. What happens if you run a pressure washer without water?

Despite the fact that pressure washers can be started without water, it is not recommended. Water serves as a lubricant and a cooling agent for the pump. Pumps that are started without the lubricating and cooling characteristics of water will fail prematurely.

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