What preventative maintenance is the most important for a pressure washer?
Most pressure washer pump failures can be prevented by doing a few specific actions every time you use your pressure washer. This preventative maintenance can help your pump run more efficiently and last longer, reducing the need for time-intensive repairs down the line. Continue reading to learn our top tips for in-season care of your pressure washer pump.
Step 1: Inspect Before Every Use
A quick check before you start can catch small problems before they turn into bigger, more expensive ones.
Before each use, check:
- Hoses, fittings, connections, and the inlet screen
- That connections are clean and secure
- Engine oil and pump oil levels
- Signs of water or oil leaks
- Damaged, kinked, or cracked hoses
Once the engine starts, pay attention to how the pump sounds and runs. Pulsing pressure, shaking, knocking, leaks, or weak performance can all be signs that something needs attention.
Catching a clogged inlet screen, a leaking seal, a loose fitting, or a damaged hose early can help prevent a larger repair later.
Step 2: Keep Water Flowing
Water flow matters on both sides of the pump, going into the pump and moving through it while the pressure washer is running.
Give the Pump Enough Water
Every pressure washer pump needs a certain amount of water to work properly. This is measured in gallons per minute (GPM). Your water supply should be able to match or exceed your pump's required GPM.
If the pump does not get enough water, it can become water-starved. This can cause poor performance and increase wear on valves, seals, and other internal parts.
To keep a steady water supply:
- Use a quality 3/4-inch garden hose when possible
- Keep the inlet filter clean
- Turn the faucet all the way on
- Avoid kinked, damaged, overly long, or narrow hoses
- Make sure your water source can meet your pump's GPM requirement
Always turn the water on and allow it to flow through the pump before starting the engine. Never allow the pump to run dry.
Watch Out for Expandable Hoses
Expandable, or pocket-style, hoses are convenient, but they do not always supply enough water for a pressure washer.
A properly supplied expandable hose should stay firm and fully expanded while you spray. If it starts to soften or shrink, stop and check your water supply. The pressure washer may be pulling water faster than the hose or faucet can provide it.
Don't Leave the Pump Sitting in Bypass
Water flow also matters when you stop spraying.
When you let go of the spray gun trigger, water keeps moving inside the pump instead of flowing out through the nozzle. This is called bypass mode.
During bypass, the same water continues circulating through the pump and can heat up quickly. Excessive heat can damage seals, valves, O-rings, and other pump components.
The main rule to remember: do not leave the pressure washer in bypass for more than about 60 seconds. If you need a longer break, shut the engine off instead.
An overheated pump can also experience thermal shock when fresh cold water enters the pump again. This rapid temperature change can crack ceramic plungers and damage other internal components.
Learn more in our Why Ceramic Pump Plungers Crack: Thermal Shock vs. Freezing Damage guide.
Step 3: Shut Down and Protect the Pump the Right Way
What you do after each job matters just as much as how you use the pressure washer. Water, detergent, and debris left inside the system can contribute to corrosion, buildup, sticking components, and other problems while the machine sits.
Follow these steps after every use:
- Flush out chemicals. If you used the chemical injector, run clean water through the system for 1–2 minutes before shutdown to rinse out detergent or chemical residue.
- Shut down. Turn off the engine, then turn off the water supply.
- Relieve the pressure. Squeeze the spray gun trigger until the trapped pressure is released.
- Disconnect the hoses. Remove both the garden hose and the high-pressure hose.
- Drain the water. Get as much water as possible out of the pump, hoses, gun, and accessories.
- Check for problems. Look for leaks or anything unusual you noticed while using the pressure washer.
- Protect the pump before longer storage. If the pressure washer will sit unused for more than two weeks, apply pressure washer Pump Guard.
- Store it properly. Keep the pressure washer somewhere clean, dry, and protected from freezing temperatures.
Why Pump Guard Deserves Its Own Step
Pump Guard, also called pump saver, is a protective fluid made specifically for pressure washer pumps.
SIMPSON 80130 Pump Guard is recommended when the pressure washer pump will not be used for longer than two weeks.
What it does for your pump:
- Lubricates pistons and seals during storage
- Helps protect the pump head and other internal components
- Provides antifreeze protection down to -25°F
- Can be used with both gas and electric pressure washers
The 80130 Pump Guard comes in a 4 oz can and connects through a 3/8-inch NPT inlet.
Don't Forget Winter Storage
The steps above cover in-season care. Freezing weather requires some additional preparation before the pressure washer is stored for the winter.
Water trapped inside the pump can freeze, expand, and damage ceramic plungers, seals, the manifold, and other internal components.
Before freezing temperatures arrive, make sure the pressure washer is properly drained and protected for storage.
For a full walkthrough, see our guide: How to Winterize a Pressure Washer.
Quick Recap: 3 Steps to a Longer Pump Life
| Stage | What to Do |
| Before you start | Inspect hoses, fittings, the inlet screen, oil levels, and look for leaks or damage. |
| While you work | Give the pump enough water, never run it dry, and avoid leaving it in bypass for more than about 60 seconds. |
| When you're done | Flush chemicals, relieve pressure, drain the system, and protect the pump before longer storage. |
Inspect. Operate. Protect. A few minutes of pressure washer pump care can help reduce unnecessary wear and catch small problems before they become expensive repairs.
Frequently Asked Questions
How long can a pressure washer sit in bypass mode?
Try not to leave the pressure washer in bypass for more than about 60 seconds. If you need a longer break, shut the engine off instead of leaving the pump running with the trigger released.
Do I need Pump Guard if I live somewhere warm?
Pump Guard is not only used for freezing temperatures. It also lubricates pistons and seals and helps protect internal pump components while the pressure washer is stored.
How often should I use Pump Guard?
SIMPSON recommends using the 80130 Pump Guard when the pressure washer pump will not be used for longer than two weeks.
Why does my pressure washer lose pressure or feel weak?
Low water supply is one possible cause. Check that the garden hose is not kinked or restricted, the faucet is fully open, the inlet screen is clean, and the water source can supply the pump's required GPM.
Need Help with Your Pressure Washer?
Allparts Equipment & Accessories carries pressure washer pumps, replacement parts, repair components, and maintenance products, backed by a team that understands how these systems work.
Not sure which part you need? Text a photo of your pump, model number, or part to 269-447-0412.
Call: 269-685-4123
Text a Photo: 269-447-0412
Visit: www.allpartsinc.com
Parts, tips, and support from Allparts Equipment & Accessories.
