A pressure washer spark plug is the only part on the machine that keeps a written record of how the engine has been running, and the firing end is the record: light tan or grey is correct, dry black soot is rich, wet and black is oil, wet and smelling of petrol is flooding, chalky

A pressure washer recoil starter fails in four distinct ways, and the one that sends most people to the parts page — a cord that will not move at all — is usually not the starter. It is the pump, sitting there holding water it was never told to let go of. Westinghouse prints the

Pressure washer pressure too high is almost never the pump deciding to make more pressure. It is a restriction somewhere downstream of it — a nozzle orifice too small for your machine’s flow, a tip half blocked with grit, an unloader wound up to hide a different fault, or a gauge that is quietly lying

A pressure washer won’t prime when the air sitting inside the pump has no way out of the machine — and the thing most likely to be blocking its exit is the spray tip still clipped onto the end of the lance, which is exactly why the manufacturers tell you to take it off before

A pressure washer backfiring at the exact moment you switch it off, at full throttle, is not a fault at all — that bang is unburnt fuel lighting in a hot silencer, and the fix is a habit rather than a part: throttle down, let it idle for a few seconds, then stop it. That

A pressure washer runs rough for five reasons, and the quickest way to separate them is to notice what the load was doing at the moment it happened — because this is the one engine in your garage whose load swings from everything to almost nothing every time you let go of the trigger. That

If the engine runs perfectly and the pump does absolutely nothing — no water, no pressure, not a sound from the pump end — a broken pressure washer pump coupler is the mechanism to check first, because the drive between the two has come apart and the pump is simply no longer being turned. A

**A pressure washer won’t start after winter because of a chain the off-season builds in a fixed order — the fuel goes stale first, that fuel leaves varnish in the carburettor second, water left in the pump freezes third, and a scatter of small winter damage arrives across the whole season — and the only

If your pressure washer won’t run without choke after the engine has properly warmed up, it is running lean — the choke is strangling the air side to make up for fuel that is not arriving, which makes it a symptom you are reading, not a setting you have found. This is the cleanest diagnostic

A pressure washer check valve is a spring-loaded one-way valve inside the pump head — six of them on a three-plunger pump, an inlet and a discharge pair above each plunger — and when one stops seating, the machine does not simply die. It fails in one of four recognisable ways, and which way tells