When Should I Change the Oil in My Pressure Washer Pump?

Running clean oil in your pressure washer's pump is one of the best ways to ensure long life and efficient performance from your machine. The pump is the heart of your pressure washer and runs at high temperatures. But does your pump oil actually need to be changed? The pumps of most pressure washers under $400 have a pump you never do any maintenance on. They are filled with oil at the factory and permanently sealed. In other pumps, the pump oil should be changed on a regular basis with quality pressure pump oil and kept at the recommended level. Your machine's manual is your best source for the information you need.

Cleaning with high pressure
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When Should I Change the Oil in My Pressure Washer Pump?

Pressure Washer Pump Oil Change

Be sure to consult your manual to learn whether and when pressure washer pump oil should be changed. During normal service, replace the oil every 200 to 250 work hours, about every three months if you use your machine often, and at least every year if not. One way to remember to change the oil in your pump is to schedule it along with changing the oil in the pressure washer's engine.

Pressure Washer Pump Oil Maintenance

Your manual will tell you if changing the pressure washer pump oil is a regular part of your required mainetance on the machine. Keeping up with maintenance on any machine is important to extending its life and keeping the warranty.

If your manual instructs you to change the pressure washer pump oil, here is the way to proceed. Place a drain pan under the machine below the pump. Remove the pump oil filler cap and the pump oil drain plug. Allow the oil to drain completely from the pump. To catch the oil without making a mess, on some models you may have to use a funnel or piece of tubing to guide the used oil to the drain pan. Replace the drain plug and fill the pump with DP70 pump oil. Use only the quantity specified in your pressure washer's manual for your pump. If you're not sure, measure how much oil you drained and replace with that amount. Most pumps have an oil window or sight glass on the side of the pump, with a mark or red dot indicating the proper level for the oil.

Considerations for Pump Oil

Change your pump oil if it looks milky, changes color or has visible particles. Always use oil specifically designed for pressure washer pumps. Good pressure washer pump oil is non-detergent, non-foaming and has rust inhibitors. Never overfill the pump with oil, which could lead to leaks caused by damaged seals. Never pour used oil into a storm drain or sewer. Dispose of old oil properly by recycling or taking it to a used-oil collection center. Always follow manufacturer recommendations and instructions for types of oil, locations of oil filler caps and drain plugs and oil quantities.