Skip to Content

Pressure Washer Running Rough, What to Do?

It is a lovely day, and you get up ready to do some pressure cleaning only to find out that your cleaning is roughed up. Your pressure washer is running slow, and the pressured is not as high as it should be. What to do? Don’t worry! We have got you covered up with this article about what potential problems might be there and how to deal with them the easy way.

What Are The Causes?

  1. A restricted carburetor due to the residue fuel clogged up in it.
  2. A clogged fuel filter due to old or bad fuel.
  3. A clogged fuel cap can create a vacuum in the fuel tank, causing the engine to rough up.
  4. A dirty air filter can cause insufficient air supply to the combustion.
  5. An incorrect nozzle or a nozzle that has worn out.
(CC BY-SA 2.0) by Ryan Harvey

A rough-running pressure washer is basically due to incomplete combustion in the engine, failing to provide the required thrust to the water channel. The combustion problem can be due to several reasons. Here we go through them:

The pressure washer may also be rough if the hot water has been consistently used for working or if the water quality isn’t good so that scaling might occur in the nozzle.

This might be a lot to take in, but don’t worry, we have got you covered up as we promised. So here are some home scale troubleshooting points that you can easily follow.

Common Troubleshooting Steps:

Pressure washers commonly involve combustion, which is a violent process in the definition. So significant issues are related to adequate fuel, air, spark, and filter mechanisms. Here, we address them one by one for the easy way.

1. A Restricted Carburetor:

The residue that is left in the fuel tank due to old fuel is the primary cause. The carburetor is a crucial component responsible for providing the correct air-fuel mixture and leading up to the combustion chamber. The clogging can cause the pipes to thin down, providing insufficient fuel. In extreme cases, the engine power drastically reduces and starts making a gurgling noise.

– Solutions:

  • Fresh fuel: Using fresh gas when the washer is used can significantly solve all the major problems. Keep the tank empty, and don’t fill it up with unnecessary fuel.
  • Fuel Stabilizer: Fuel stabilizers are used in a mixture with the added fuels. These keep the density of fuel consistent and help avoid residue creation at the bottom. The stabilizer contains additives that serve as chemical agents, enhancing fuel residual life.
  • Carburetor Cleaning Kit: Cleaners like WD-40 are readily available in the market, acting as anti-rust agents and cleaning the grease. If the problem is somewhat more significant, carburetor components like seals and clips can be replaced or the carburetor in total too.

2. A Clogged Fuel Filter:

The fuel filter is the final shield before the fuel enters the combustion process. As the name suggests, the filter is responsible for stopping impurities, dirt, and harmful objects like insects, residues and let the fuel pass only. If bad fuel comes in contact, it may cause the filter to get clogged up and lose functionality way before its expected lifespan. In all this, the engine action gets rough.

– Solutions:

  • Clean fuel: It is always preferable to use clean fuel with fuel stabilizers when the pressure has to be used. Extra fuel in the tank will still cause problems.
  • Replacement: Like all filters, the fuel filter should be replaced annually unless the black residue is visible to the naked eye.

3. A Clogged Fuel Cap:

As fuel is consumed, the fuel level in the tank is reduced. So, the fuel cap has vents that allow for air to pass through to the tank. If these vent holes are blocked by buildup or debris, the air cannot enter the fuel tank. It creates a vacuum that can also cause the engine to run rough.

– Solutions:

  • Acid Cleaning: The fuel cap can be dipped in a bath of acid readily available from the market, which exposes the vent holes and unclogs them efficiently.
  • Replacement: A more straightforward solution will be to replace the fuel cap, which is readily available as a spare part in the market.

4. A Dirty Air Filter:

As with all machinery requiring pressure, pressure flow sucks in a stream of air to throw with the water to speed and force. Exposed to the unpretentious atmosphere, the air filter gets dirty, exposed to dirt, insects, and other substances in the atmosphere. This can cause the washer to run rough by preventing smooth airflow to the carburetor.

– Solutions:

  • Cleaning: The air filter can be cleaned easily using a roots blower or pneumatic pressure cleaner if dirt is visible. However, it is advisable to clean it once in 2 months or when used after a long gap.
  • Replacement: Generally, the air filter should be replaced annually. This enhances the life of the carburetor too.

5. Nozzle Issues:

The nozzle is the central part where water ejects out of the machines. The nozzle size mainly determines the range, force, and speed of the water gushing out. Using an incorrect nozzle size reduces the pressure or pressurizes it to the extent that it can damage the washer. A nozzle that gives a range of 3-7 feet is suggested in the books. Also, continuous use may cause the nozzle to be worn out, leading to rough running.

– Solution:

  • Nozzle Maintenance: The ideal solution to this problem is choosing a suitable nozzle to replace the worn-out nozzle and to ensure that you use the same temperature water for your cleaning each time (ideally cold water only).

Some Additional Problems:

● Water Quality:

Another cause for a rough working pressure washer can be the water quality. If the water quality is poor, containing heavy metals and too many minerals dissolved, it can cause scaling in the washer’s nozzle and tubing. This reduces the water channel space.

– Solution:

It is mostly recommended to use pressure washers where suitable soft water is available. However, if such is not the case, water from a purifying tank can be used up where additives are added to enhance the water quality and reduce its hardness. The washer must be serviced regularly, cleaning all its nozzles with acid and water bath removing the scales.

● Water Temperature:

If the temperature of water used for cleaning is high, it can cause issues. Generally, things expand on heating and compress on cooling. Regularly using hot water can cause the seals found in various parts of the washer to loosen. This can cause leaking in addition to a rough performance.

– Solution:

Coldwater should be the preferred fluid while using a pressure washer. The hot water should only be used to service and clean the parts.

Related Questions:

● How do I fix my pressure washing surging?

Surging is most commonly due to blocked, or semi blocked water channels. In this case, remove the nozzle and valves of the washer. Clean them with a cleaning kit. Also, check the inlet hose and filter if it needs some cleaning to be done.

● How do you know if your unloader valve is bad?

If stalling occurs in a gas or diesel-powered engine whenever the operator ceases to use the washer, it gives a good indication of unloader valve failure. The clogging causes the buildup of pressure and locks the internal components, which prevents the rotation of the powered engine shaft. An ideal way would be to keep the washer in constant monitoring and unloader valve replacement when it requires.

● How long should a pressure pump last?

Generally considering low-cost pressure pumps are made up of using low-quality pumps. So, these pumps have a life expectancy of 60 to 100 hours of use, which may be stretched depending on the service and maintenance these pumps are given. For a high-quality pump, this life expectancy drastically increases to around 500 hours. So depending on your pump quality, it can last anywhere between this range.

Final Remarks:

As the famous proverb goes, “Prevention is always better than cure.” The same is the case with pressure washers. We can generally say that the instrument’s performance roughness is closely linked with the machine’s maintenance and service. A better quality fuel with combustion enhancers ensures smooth combustion. Regularly tuning carburetor and good regular service of all filters and valves provides more extended and smoother functionality. Like any other machinery, proper care of these washers will enhance their life and avoid any undesired issues.