How to Use Soap with a Simpson Pressure Washer

On this page (8 sections)

1. How do you use soap with a Simpson pressure washer?
2. Where does detergent go on a Simpson pressure washer?
3. Which nozzle should you use for soap?
4. What detergent works in a Simpson pressure washer?
5. Can you use a foam cannon with a Simpson pressure washer?
6. Why won't a Simpson pressure washer draw soap?
7. How should you rinse and care for the soap system?
8. What is the safest way to apply pressure washer soap?

To use soap with a Simpson pressure washer, put pressure-washer-safe detergent in the compatible onboard tank or siphon container, then apply it with the low-pressure soap nozzle. Follow your model's manual for the correct detergent, dilution, and setup.

Simpson washers can feed detergent through different arrangements, so first identify the one your model uses. The soap tank or pickup tube, detergent, and nozzle must work together for the washer to draw solution.

How do you use soap with a Simpson pressure washer?

Connect the detergent feed, select the soap nozzle, apply detergent, let it work as directed, and rinse with clean water. Use your manual's instructions for the exact connections and dilution.

For another brand-specific walkthrough, see Sun Joe soap guide.

1. Turn off the washer and relieve pressure before changing accessories.
2. Fill the onboard soap tank, if your model has one, or place the pickup tube in the detergent container.
3. Attach the low-pressure soap nozzle specified in the manual.
4. Start the washer and apply detergent from the bottom up, avoiding areas that should stay dry.
5. Allow the detergent to dwell only as directed on its label, and don't let it dry on the surface.
6. Turn off the machine, change to a rinsing nozzle, and rinse thoroughly.

Keep detergent out of eyes, plants, and drains where the label or local rules require care. Don't spray people or animals, and use the washer's instructions for safe startup and shutdown.

For the general process, see how to use detergent with a pressure washer. Simpson model instructions take priority when they differ from general steps.

Where does detergent go on a Simpson pressure washer?

Put detergent in the onboard tank if your Simpson model has one; otherwise, use the detergent pickup tube or siphon arrangement specified in its manual. Never pour soap into the water inlet or pump.

Onboard tanks hold detergent for the washer to draw through its designed feed path. Close the cap securely and use only the detergent type and dilution allowed by the manual.

For a siphon system, place the pickup tube in the detergent solution and keep its end submerged while applying soap. Don't kink or crush the tube, and remove it from the solution when you're done.

If you aren't sure which system your washer has, check the model number and manual before adding detergent. Simpson models can differ in their setup, and a compatible tank or tube matters more than the brand name on the soap.

Which nozzle should you use for soap?

Use the low-pressure soap nozzle or detergent setting specified for your Simpson model. A high-pressure nozzle may prevent a siphon system from drawing detergent.

Nozzle colors are not universal across all pressure washers, so confirm the nozzle function in your manual rather than relying on color alone. Turn off the washer and release pressure before swapping nozzles.

A soap nozzle applies detergent at lower pressure, which helps the washer draw from its tank or pickup tube. Switch to a suitable rinsing nozzle after the detergent has had the label's recommended contact time.

For a closer explanation, read what a soap nozzle on a pressure washer does. Don't confuse a soap nozzle with a foam cannon, which attaches separately at the spray gun.

What detergent works in a Simpson pressure washer?

Choose a detergent labeled for pressure washers and suitable for the surface you're cleaning. Use the dilution and application method printed on its label, along with any Simpson restrictions.

A product designed for car washing may suit vehicle paint, while a general-purpose pressure washer detergent may cover hard surfaces. Match the soap to the job, and test an inconspicuous spot if the surface could be sensitive.

KÄRCHER describes its multipurpose detergent for surfaces including concrete, patios, decks, cars, boats, homes, and fences. It says one gallon of concentrate can make up to 40 gallons of detergent; follow the container's label for dilution.

Don't assume a broad-use detergent is right for every surface.

If you want a vehicle soap, Adam's Polishes Car Wash Shampoo is described as pH neutral and suitable for a bucket, foam gun, or foam cannon. Follow its directions and your vehicle-care needs.

Don't put a soap in the tank just because it makes suds. Household dish soap and other cleaners may not be suited to pressure washer seals, detergent pickup, or the surface being cleaned.

For help choosing a soap by surface, see what soap you can use in a pressure washer. If you're considering a homemade mix, review homemade pressure washer soap before putting it in the washer.

Can you use a foam cannon with a Simpson pressure washer?

You can use a foam cannon when its fitting and operating requirements match your washer and spray gun. It attaches at the gun, so it doesn't use the same feed path as an onboard tank or siphon tube.

Check the cannon's connector type and your pressure washer's requirements before buying or connecting it. The DUSICHIN SFL-001 has a 1/4-inch quick-disconnect fitting, and its stated requirements are 6 GPM flow and up to 3,000 PSI maximum pressure.

Confirm your washer meets those requirements and that you have a compatible connection.

The cannon's detergent container and adjustable nozzle let you apply foam independently of a tank-based soap feed. Follow the soap label and cannon instructions for mixing and use.

For car washing, compare this setup with how to use soap in a Ryobi pressure washer. You can also see best Westinghouse pressure washer soap and how to use soap with a Greenworks pressure washer for other brand-specific detergent setups.

Why won't a Simpson pressure washer draw soap?

Check the nozzle, pickup tube, detergent level, and dilution first. A siphon system often needs the designated low-pressure nozzle to pull detergent.

Turn the machine off before inspecting the connection. Make sure the tube is attached, open, and submerged in detergent, then check for clogs or kinks.

If the detergent is thick or mixed too strongly, dilute it only as its label directs. Avoid forcing detergent into the system or taking apart the pump; use Simpson support or a qualified repair shop if the feed still won't work.

How should you rinse and care for the soap system?

Rinse the cleaned surface thoroughly, then flush the detergent feed with clean water if your manual directs it. This helps clear leftover solution from the pickup tube or tank.

Remove detergent from the system after the job rather than storing it in the washer. Empty the tank or take out the pickup tube, then follow the model's storage and maintenance steps.

Keep the soap nozzle and tube clean, and don't use tools that could damage a small opening. Store detergent in its original container with the label intact.

What is the safest way to apply pressure washer soap?

Use the detergent and nozzle approved for your model, keep the spray pointed away from people, and follow the surface and detergent labels. Wear the protective gear those instructions call for.

Avoid spraying electrical parts, delicate finishes, or surfaces that could be damaged by water or detergent. Keep the nozzle moving and don't allow detergent to dry on the surface.

Choose the tank or siphon method described in the manual, and use a foam cannon only when it fits the washer's requirements. For a Simpson pressure washer, the model-specific manual is the best guide to detergent delivery.

Frequently asked questions

Can I use any soap in a Simpson pressure washer?

No. Use detergent labeled for pressure washers and suitable for the surface you plan to clean.

Check your Simpson manual for the approved feed method and dilution, and avoid household dish soap unless the washer or detergent maker specifically approves it.

The right soap depends on the surface and cleaning task.

Why isn't my Simpson pressure washer drawing soap?

A Simpson washer may not draw soap if the soap nozzle isn't installed, the detergent pickup tube is loose or blocked, or the detergent is too thick or diluted incorrectly. Check the manual, confirm the tube reaches the solution, and make sure the nozzle and feed method match your model.

Do I need a special nozzle to apply soap?

Usually, yes. Detergent siphon systems commonly need the low-pressure soap nozzle to draw and apply solution.

Follow your Simpson manual because nozzle colors and configurations can vary by model, and don't use a high-pressure nozzle to apply detergent.

Can I use a foam cannon with a Simpson pressure washer?

A foam cannon can work if its connector and operating requirements match your washer. Check the washer's manual and the cannon's fitting, flow, and pressure requirements before connecting it.

A foam cannon attaches at the spray gun and works differently from an onboard detergent tank or siphon tube.