Karcher Pressure Washer Won’t Start – What To Do?

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Karcher offers different pressure washers, including the K1, K2, K2 Compact, and the K5 Premium. Although these models present powerful features, they’re not invulnerable to damage and might not start. Now you're wondering why your Karcher pressure washer doesn't start. Also, what can you do with it? We researched for you, and here's what we found.

One of the reasons why a Karcher pressure washer doesn’t start is because of an airlock. If so, you need to bleed the air from the unit to restore its serviceability. The steps for this operation are:

  1. Press the yellow button to disconnect the hose from the wand.
  2. Drain the water from the washer for about 5 minutes.
  3. Reconnect the hose and test if the machine’s motor starts.

Oftentimes, a Karcher pressure washer failing to start may come from other sources. Keep reading to learn more about the possible reasons for this pressure washing machine to break down. We’ll also tackle other relevant yet important information, such as the possible lifespan of a pressure washer from Karcher.

Cleaning the patio check using a pressure washer, Karcher Pressure Washer Won't Start - What To Do?

Why Will My Karcher Pressure Washer Not Start?

You can check a few things in your Karcher pressure washer to identify the reason why it doesn’t start. Aside from its failure to start, investigate the device for other symptoms like gunk buildup or a humming sound. That way, you can verify the source of the problem.

A Karcher pressure washer in the backyard

Here are some reasons why a Karcher pressure washer doesn’t start:

Defective Spark Plug

The spark plug can accumulate heavy carbon over time. Additionally, this component might become cracked because of exterior forces. Use a spark plug tester to check if this part is the faulty element.

Check out this spark plug tester on Amazon.

Clogged Carburetor

Leftover fuel in the carburetor may solidify over time, causing gunk buildup. The sticky substance can block the engine from starting. Think about replacing this part if extensive damage from the residue occurred.

Check out this replacement carburetor for Karcher pressure washers on Amazon.

Broken Flywheel Key

The flywheel key is responsible for engaging the flywheel, which is a wheel that moderates the machine’s motor speed. Strong water pressure may enter the washer’s internals, harming the flywheel key in the process.

Make sure to consult the product’s manufacturer to check if the replacement flywheel key you’re about to purchase is compatible with your Karcher pressure washer.

Check out this OEM flywheel key on Amazon.

Faulty Ignition Coil

The ignition coil is in charge of sending voltage to the spark plug when turning on the engine. A pressure washer’s motor won’t start if the ignition coil is defective. Use an appropriate testing tool to check if this part is the reason why the washer doesn’t start.

Check out this ignition coil tester on Amazon.

Malfunctioning Capacitor

Capacitors help pressure washer motors reach optimal efficiency during their startup phases. If these parts are broken or possess damages, pressure washer engines won’t ignite. Use a capacitor tester to verify the damage or lack thereof for this part.

Check out this capacitor tester on Amazon.

If you need more help with other Karcher pressure washer issues, watch the video below:

How To Repair Karcher Pressure Washer Won’t Turn On?

A Karcher pressure washer used in cleaning a pool

Take note that the solution to repairing a Karcher pressure washer that fails to start depends on the faulty or broken part. Moreover, it’s advisable to consult your owner’s manual to know the location of the washer’s parts since different models possess varying internal frameworks.

One of the reasons why Karcher pressure washers act up is because of a failsafe mechanism. Some of the brand’s pressure washers won’t start if the machine accumulates significant air, turning on their airlocks. If so, the possible solution to this problem is to bleed the air out of the washers.

Before attempting repairs to your Karcher pressure washer, make sure that the power is in the off position. Also, unplug the device from the mains to prevent electrocution. The last part of the preparation phase is to turn off the water but leave the hose connected to the washer.

After completing the initial arrangements, proceed with the next step of the repair operation:

  1. Disconnect the water hose from the wand. Some Karcher pressure washers will have a yellow button that allows you to disconnect the hose easily.
  2. Drain the water from the washer. Leave the hose disconnected for about 5 minutes after water no longer comes out to help remove the air buildup.
  3. Reconnect the hose and test if the pressure washer turns on normally.

Keep in mind that the steps mentioned above may not work for every Karcher pressure washer. This repair job may also not work if the device accrued serious damage. If so, you may need to replace some parts or substitute the unit with a new model.

You can also watch the video below to see the steps mentioned above in action:

After a successful repair, you might be thinking about using your pressure washer on your garage floor. If so, read our post on that topic for you to arrive at a sound decision.

Check out this product on Amazon.

How Long Can You Run A Karcher Pressure Washer?

The maximum length for a Karcher pressure washer to run efficiently typically depends on its main power source. Karcher's gas-powered models allow users to pump water up to 100 feet with a high-pressure hose. On the other hand, the brand's electric variants may encounter reduced performances after going past the 60-foot mark.

How Long Does A Karcher Pressure Washer Last?

A man using a Karcher pressure washer for cleaning the brick patio

A Karcher pressure washer will usually last about 500 hours of cumulative operating time before needing significant repairs or replacements. That period should translate to about 10 years for the average homeowner since pressure washer usage may not be as extensive as commercial use.

Buying a Karcher pressure washer from the manufacturer or a reliable retailer may grant you a limited warranty for the product. This guarantee may include free or low-cost parts, repairs, and replacements if the washer malfunctions from natural and uncontrollable causes.

Here are some of Karcher’s pressure washers and their relatively common warranty periods:

  • K2: 2 years
  • K3: 3 Years
  • K4 series: 3 years

Many homeowners may not need to use their pressure washers extensively. But you might be thinking about using these machines to clean large surfaces, such as your home’s vinyl siding. If so, read our post on power washing vinyl siding to learn more about that topic.

Will Hot Water Ruin A Pressure Washer?

Plugging in the hose for a pressure washer

It’s not ideal to use hot water with a pressure washer, as some DIY community members mentioned. You should find the ideal water temperature to use in a pressure washer in its operations guide or owner's manual. Otherwise, consult with the machine’s manufacturer.

Still, many pressure washers can handle hot water up to about 120 degrees Fahrenheit. Higher temperatures may cause serious problems to the machine. However, you can purchase a hot water pressure washer if you're adamant about going through with this route.

Check out this hot water pressure power washer on Amazon.

Final Words

Bleeding the air out of a Karcher pressure washer may restore its serviceability. Complete this job by letting water flow out from its hose, which should also push air out of the machine. Have the pressure washer serviced or replaced if the problem persists.

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