Introduction
This manual provides essential instructions for the safe and effective installation, operation, and maintenance of your CAT Pumps Pressure Washer Pump, Model A1573021. Please read this manual thoroughly before attempting to install or operate the pump. Retain this manual for future reference.
Safety Information
Always observe the following safety precautions to prevent injury or damage to the equipment:
- Read all instructions: Familiarize yourself with the pump's functions and operating procedures before use.
- Wear appropriate safety gear: Always use eye protection, gloves, and other personal protective equipment as required.
- Disconnect power: Ensure the pressure washer's power source is disconnected before performing any installation, maintenance, or service.
- Use with compatible systems: Verify that the pump's specifications (PSI, GPM, power requirements) are compatible with your pressure washer unit.
- Keep clear: Maintain a safe distance from moving parts and high-pressure spray during operation. Keep children and bystanders away from the work area.
- Proper ventilation: If used with a gas-powered engine, ensure adequate ventilation to prevent carbon monoxide buildup.
Product Overview
The CAT Pumps Pressure Washer Pump, Model A1573021, is designed for efficient pressure washing applications. This direct drive pump is pre-plumbed and pre-tested for convenience and reliability. It is engineered to provide a fast changeover, even in the field.

Image: The CAT Pumps Pressure Washer Pump A1573021, showing the main pump body, brass manifold, and inlet/outlet connections.
Key features include:
- Pre-plumbed and pre-tested for immediate use.
- Designed to fit 4-bolt motor face plates for direct drive systems.
Setup and Installation
Follow these steps for proper installation of your new pump:
- Preparation: Ensure the pressure washer unit is turned off and disconnected from its power source. Drain any remaining water from the old pump and hoses.
- Remove Old Pump: Carefully detach the old pump from the motor. Note the orientation of the pump and any connections.
- Mounting: The A1573021 pump is designed to fit 4-bolt motor face plates. Align the new pump with the motor's mounting holes. Bolts are not included with the new pump; use the existing bolts from your old pump to install the new pump securely.
- Water Inlet Connection: Connect your water supply hose to the pump's inlet. Ensure a tight, leak-free connection. A water filter should be used on the inlet to prevent debris from entering the pump.
- High-Pressure Outlet Connection: Connect your high-pressure hose to the pump's outlet. Ensure this connection is also tight and secure.
- Chemical Injector (if applicable): If your unit uses a chemical injector, connect it according to your pressure washer's instructions.
Compatibility Note
While this product may be listed for electric pressure washers, it is important to note that this item is typically for use with gas, not electric drive systems. Please verify compatibility with your specific pressure washer's motor type and power requirements before installation and operation to ensure safe and correct functionality.
Operating Instructions
Once the pump is installed and all connections are secure, follow these steps for operation:
- Connect Water Supply: Turn on the water supply to the pressure washer. Allow water to flow through the pump and out the high-pressure hose (without the spray gun attached) for approximately 30 seconds to purge air from the system. This primes the pump.
- Attach Spray Gun: Connect the spray gun to the high-pressure hose.
- Start Pressure Washer: Turn on the pressure washer's motor. Allow the engine/motor to reach full operating speed.
- Begin Cleaning: Squeeze the trigger on the spray gun to begin spraying. Adjust nozzles as needed for your cleaning task.
- Shut Down: To stop operation, release the spray gun trigger. Turn off the pressure washer's motor. Turn off the water supply. Squeeze the spray gun trigger to release any remaining pressure in the system.
Maintenance
Regular maintenance ensures the longevity and optimal performance of your pump:
- Inspect Connections: Before each use, check all hoses and connections for leaks, wear, or damage. Replace any worn or damaged components immediately.
- Clean Water Filter: Regularly inspect and clean the water inlet filter to prevent debris from entering and damaging the pump.
- Check for Oil Leaks: Periodically inspect the pump for any signs of oil leaks. Address any leaks promptly.
- Winterization (for cold climates): If storing the pressure washer in an area where temperatures may drop below freezing, winterize the pump to prevent damage. This typically involves flushing the pump with an antifreeze solution or pump saver. Consult your pressure washer's manual for specific winterization procedures.
- Storage: Store the pump in a clean, dry environment when not in use.
Troubleshooting
Refer to the following table for common issues and their potential solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No water pressure | No water supply; Air in pump; Clogged inlet filter; Kinked hose | Ensure water supply is on; Prime the pump; Clean inlet filter; Straighten hose |
| Low water pressure | Insufficient water supply; Worn nozzle; Air in pump; Leaks in system | Check water flow; Replace nozzle; Prime pump; Inspect for leaks and tighten connections |
| Pump making unusual noise | Air in pump; Low water supply; Loose components | Prime the pump; Ensure adequate water flow; Check and tighten all connections |
| Water leaks from pump | Loose connections; Worn seals/O-rings | Tighten all fittings; Inspect and replace worn seals or O-rings (professional service recommended) |
If troubleshooting steps do not resolve the issue, contact customer support or a qualified service technician.
Specifications
| Specification | Detail |
|---|---|
| Brand | CAT Pumps |
| Model Number | A1573021 |
| Maximum Pressure | 3000 PSI |
| Maximum Flow Rate | 2.5 Gallons Per Minute (GPM) |
| Power Source | Corded Electric (Refer to Compatibility Note in Setup section) |
| Material | Polypropylene (PP), Stainless Steel |
| Item Weight | 11.62 pounds |
| Package Dimensions | 14.25 x 10 x 9 inches |
Warranty and Support
For warranty information, technical support, or service inquiries, please contact CAT Pumps directly or refer to their official website. Keep your purchase receipt and model number (A1573021) available when contacting support.





