In the event that the pressure washer is not to be used for an extended period of time (winter) store in a heated space or anti-freeze the unit. With water off run the machine until the float tank is near empty. Fill with 50% mix of water and anti freeze and run until anti freeze appears at the high pressure outlet. Cycle gun a couple of times to include bypass loop in the flow. If the pressure washer includes an air blow out device it may be blown out with compressed air in addition to using the anti freeze solution. Check & drain any water supply filter housings that may have been overlooked.

On direct feed pressure washers (no float tank), use a 5 ft garden hose to draw the anti freeze mix from a bucket or blow out the unit with compressed air until only air and no water is discharged. Blow out bypass loop also to reduce risk of water return to the pump head area.

Use aftermarket fuel stabilizers for fuels. To prevent carburetor problems shut off fuel to engine and run until carburetor fuel bowl is depleted. Remember to turn key switch off. Disconnect 12 V battery terminals. Negative side should be sufficient to reduce long-term battery drain. Protect the pressure washer from rain & snow. Confirm exhaust pipes are covered or not in a position that will allow water intrusion into the engine.

For your trailer mounted pressure washer system, consider jacking & blocking to reduce risk of tire damage or deflection problems.