The after-every-use routine
- Release the pressure. Shut the machine off, turn off the water, and squeeze the trigger to bleed off the pressure still stored in the system before you disconnect anything.
- Flush out the detergent. If you used soap, run clean water through the detergent system until it comes out clear — leftover detergent dries and clogs the soap injector.
- Clear the spray nozzles. Pop the tips and clear each opening with the tip-cleaning wire (or a paperclip). A partly blocked nozzle is the number-one cause of weak or pulsing pressure.
- Rinse the inlet screen. Pull the small filter screen at the water inlet and rinse out the grit — a clogged inlet screen starves the pump.
- Drain the hose, gun and wand and coil the hose without kinks.
- Wipe it down and store it dry, out of direct sun and away from freezing temperatures.
Periodic checks
- Pump oil (gas units): change it after break-in and on the manual's schedule; check that it isn't milky (a sign of water getting in past a seal).
- Hoses, O-rings and seals: inspect for cracks, bulges and leaks, and replace worn O-rings on the quick-connects — a tiny leak bleeds off pressure.
- Engine basics (gas): keep up with the engine oil, air filter and spark plug, and don't store it with stale fuel in the tank (use fuel stabilizer or run it dry).
- Descale: if you're on hard water, periodically run a descaling solution through to clear mineral buildup that narrows the lines.
Winterizing — the step that saves the machine
This is the most important maintenance a pressure washer gets, because freeze damage is usually fatal. Before the first frost: disconnect the hoses, drain all the water from the pump, gun and wand, then run pump saver / antifreeze made for pressure washers through the inlet until it comes out of the pump. Water trapped in the pump freezes, expands, and cracks the housing — and a cracked pump usually costs more than the washer is worth. Even in a heated space, draining it keeps the seals from drying out.
Electric vs. gas
Electric pressure washers are lower-maintenance: the pump is usually sealed (no oil changes), so care is mostly flushing, nozzle cleaning, and protecting it from freezing. Gas pressure washers add engine upkeep — oil, fuel, air filter, spark plug — and a serviceable pump with oil to change. Both live or die by the same two habits: flush after every use, and never let water freeze inside them.
Quick troubleshooting
- Low or no pressure: clogged nozzle, dirty inlet screen, kinked/undersized supply hose, or air in the pump. Clean the nozzle and screen first.
- Pulsing or surging: partial nozzle clog, low water supply, or trapped air — clear the tip, confirm full water flow, purge air.
- Leaking: worn O-rings at the connections or a failing pump seal.
- Won't start (gas): stale fuel, fouled spark plug, or low oil on engines with a low-oil cutoff.
- Milky pump oil: a seal is letting water in — service it before the pump fails.
The same two habits, every machine
Flush it and don't let it sit dirty or frozen — that's the whole job with a pressure washer, and the same care-and-storage logic runs through your entire kit. Our pillar guide on how to keep your cleaning equipment clean covers vacuums, mops, extractors and auto-scrubbers too. For big exterior jobs — building washes, parking lots, sidewalks and graffiti — Zusashi runs commercial-grade, maintained equipment across the GTA: see our pressure washing service or get a free quote.
Frequently asked questions
How do you clean a pressure washer after use?
Release the stored pressure with the trigger, flush clean water through to clear the detergent, clean the nozzles with a tip tool, rinse the inlet screen, drain the hose/gun/wand, and store it dry.
How do I winterize a pressure washer?
Drain all the water, then run pump saver/antifreeze through the inlet until it exits the pump. Water left in the pump freezes and cracks the housing over winter — the most common way a pressure washer dies.
Why does my pressure washer have low or no pressure?
Usually a clogged nozzle, dirty inlet screen, kinked supply hose, or air in the pump. Clean the nozzle and screen, confirm full water flow, and purge air before blaming the pump.
Why is my pressure washer pulsing or surging?
A partial clog or air in the system. Clean the spray tip, make sure the water supply delivers enough flow, clear the inlet screen, and purge trapped air with the gun open.
Do you need to change the pump oil on a pressure washer?
Gas units, yes — after break-in and on the manual's schedule (plus separate engine oil). Most electric pump units are sealed and maintenance-free. Watch for milky oil or leaks, which signal a seal problem.