my pressure washer runs but the water just dribbles out, no pressure at all.

Diagnosis

The primary cause of a "dribble" effect on the Craftsman CMEPW1900 is a failure in the water intake system, leading to cavitation. When the pump is running but cannot pull enough water to create pressure, it is usually because the internal mesh inlet screen is obstructed by sediment, algae, or calcium deposits from your home's water line. This creates a vacuum lock where the pump spins but cannot prime. You can confirm this is the issue by checking the sound of the motor. If the machine sounds like it is struggling or "hammering" (rapid clicking/pulsing), it is experiencing air pockets due to a lack of water flow. If the motor sounds smooth but the output is weak, the issue is likely a total blockage at the inlet filter or a severe kink in the supply hose preventing the 1.9 GPM (gallons per minute) flow required by the pump.

How to Fix It

Follow these precise steps to clear the intake and prime the pump:

1. Disconnect the power cord from the 120V outlet and shut off the water supply valve completely.
2. Unscrew the garden hose from the water inlet port on the machine.
3. Locate the small, circular plastic mesh filter seated inside the female threaded intake port. Use a pair of needle-nose pliers to grip the center plastic tab and pull the filter screen straight out.
4. Inspect the mesh for fine silt or debris. Use a soft-bristled toothbrush and warm soapy water to scrub the screen. If the mesh is torn or permanently clogged with mineral scale, replace it with a compatible 1/4" mesh replacement screen.
5. Reinsert the clean filter, ensuring it seats flush against the housing to prevent air leaks.
6. Reconnect your garden hose, ensuring the rubber washer is present in the hose coupling to prevent air from being sucked into the line.
7. Crucial Priming Step: Before plugging the machine into the outlet, turn the water faucet on full blast. Squeeze the trigger on the spray wand and hold it for 30-60 seconds. This purges all trapped air from the pump head.
8. Once water is flowing steadily (even without pressure) from the nozzle, plug in the machine and engage the power switch.

If That Didn't Work

• Check for Air Locks in the Hose: If you are using a hose longer than 50 feet, the pump may struggle to pull water. Try using a shorter, high-flow 25-foot hose to see if the pressure returns. Ensure there are no "low spots" in the hose where air bubbles can accumulate.
• Inspect the Nozzle Orifice: The CMEPW1900 often comes with a multi-pattern nozzle. If a tiny piece of grit is lodged in the specific nozzle orifice, it will restrict flow. Switch to a different nozzle tip or remove the nozzle entirely to see if the pump delivers a strong, unrestricted stream of water.
• Verify the Unloader Valve: If the motor is humming but not engaging the pump, the internal unloader valve may be stuck in the "bypass" position. Gently tap the side of the pump housing with a rubber mallet while the unit is running to potentially jar the valve open.
• Check for Kinked Internal Hoses: Inspect the high-pressure hose leading from the pump to the wand. If the hose has a sharp kink or a pinch point, the water cannot exit the pump, causing the pressure switch to trip and the water to simply circulate internally.

Heads Up

• Never run the CMEPW1900 "dry." Running the pump without water for even 60 seconds can overheat the seals and permanently damage the pump head.
• Always use a reinforced garden hose. Standard lightweight "expandable" hoses often collapse under the suction of the pump, cutting off water flow and causing the dribble effect.
• At the end of every season, drain all water from the pump and hose. If water freezes inside the pump manifold, it will crack the casting, resulting in a total loss of pressure.
• Avoid using a "kink-free" hose that has a very small inner diameter, as the pump requires a consistent volume of water to maintain its 1900 PSI rating.