Troubleshooting Guide for Pressure Washers

Sep 12, 2025 | Blog, Tips | 0 comments

Engine won’t start – SOLUTION

Engine switch is in ‘OFF’ Position Set throttle to ‘RUN’ position.
Pressure build-up after pulling cord Depress the trigger gun while you try to start it.
Carburetor not primed Prime carburetor.
Carburetor jets clogged Bring to shop for carb cleaning in an ultrasonic cleaner.

Won’t draw chemical

Nozzle not in chemical draw position Set nozzle to chemical.
Chemical screen is obstructed Check chemical screen, clear obstruction.
Trying to draw chemical with a h.p. nozzle inserted Switch to the black chemical/low pressure nozzle.
Injector orifice obstructed/stuck Check & clean. Poke paper clip down into chem nipple.

Pump running normally, but pressure doesn’t achieve rated values

Water supply restricted Check water supply & filter screen for blockage, kinks, leaks, etc.
Nozzle is in low PSI position (if applicable) Set nozzle to the high-pressure position.
Nozzle too large or worn Check & replace.
Pump sucking air Check that hoses & fittings are airtight.
Nozzle blocked Clean nozzle.

Fluctuating Pressure

Pump sucking air Check that hoses & fittings are airtight. Purge air from garden hose.
Garden hose inlet strainer clogged Clean & check filter frequently.
Worn seals or packing Check and replace.
Inadequate water supply Check flow available to pump.
Fouled or dirty inlet or discharge valves Clean inlet & discharge valve assemblies. Replace if damaged.

Pressure is low

Nozzle is clogged or partially obstructed Clean or replace.
Nozzle worn Check & replace.
Valves worn, dirty or stuck Check, clean or replace.
Worn piston packing Check and replace.
Inadequate water supply to unit Shorten supply hose or get one with larger diameter.
Leaky discharge hose Check o-rings on q.c. & hose itself. Replace if cracked or punctured.

Pump noisy

Water supply inadequate Shorten supply hose or get one with larger diameter.
Pump sucking air Check that hoses & fittings are airtight.
Debris in valves or valves worn Check, clean or replace.
Worn bearings Replace pump.

Presence of water in oil (milky), Water dripping from pump

High Humidity Change oil.
Piston packing & oil seal worn Check & replace oil seals.

Water dripping from pump

Fittings loose Tighten fittings.
O-rings or piston guide retainer worn Check & replace.
Piston packings worn Check and replace.

Oil Dripping

Oil seal worn Check and replace.
Loose drain plug or worn o-ring Tighten drain plug or replace o-ring. Do not over torque.

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