How do I perform oil maintenance on a pressure washer triplex pump?

This article outlines the maintenance procedure for pressure washer triplex pumps, including selecting the right oil type, SAE 30, SAE 15W-40, or ISO 68 hydraulic oil based on the pump model- and details the procedures for checking and changing oil. Note that axial cam pumps are sealed and do not require maintenance. 
 

Environment

This article applies to most professional and commercial grade pressure washers. 

Selecting the right oil for your pressure washer pump

Guidelines for selecting the right oil based on the type of pressure washer. 
 

1. Standard Triplex Pumps: For most triplex pumps, use SAE 30 non-detergent oil. 
2. Belt-Driven pressure washers: If the pressure washer is belt-driven, it requires SAE 15W-40 non-detergent oil. 
3. Specific models - XC4000 and XC4200: These specific models of pressure washers require ISO 68 hydraulic oil. 
4. Axial cam pumps are factory sealed and do not require oil maintenance. These pumps are designed to be maintenance-free, so no oil changes or refills are necessary during their operational lifetime. 

Note: The pump manufacturer oil recommendation is based off of belt driven setups. However, most of our setups, with the exception of one, are direct drive applications. The oil recommendations in the manual take into account the heat transfer from these types of applications.

Triplex pump oil maintenance procedure

Change the pump oil every 50 hours of operation. For more maintenance intervals and general maintenance information, see: Pressure Washer Maintenance: What Are the Maintenance Intervals, and What Should I Check?
 

Note: Triplex pumps are available on professional series pressure washers only. Residential pressure washers use axial cam pumps, which should not have their oil changed: What Is the Axial Cam Pump Used with Generac Pressure Washers?

 

1. Remove drain plug (A). 
2. Drain oil completely into the approved container.
3. Install the oil drain plug, do not over-tighten.
4. Remove the oil dipstick (B).
5. Fill the pump with oil.
6. Oil must be between the “L” and “H” on the dipstick. (DO NOT OVERFILL).
 

7. Install oil dipstick until finger tight.