I was pressure washing the algae off the walls of my house yesterday. I’d been at it for an hour or so when suddenly the motor started to scream at very high revs, but the water pressure fell to zero. Turned off the machine. With the motor stopped, water flows through the system and hose and filters are clear. However, when I turn the switch on, rather than the motor rev and then stop (waiting for the trigger pull to restart it), it revs/screams at far higher revs than normal. I’ve no idea what type of pump is in there, but it’s as if the paddles have been removed and the spindle is just spinning like mad without getting any ‘traction’ with the water. Any ideas gratefully received - the machine is a few years old now. Thank you very much.