What is this 'Wash' screw for?

[Herman Melville]

Can I attach a screw thread and hose to it and flush the engine?

Right now I use mufflers - this would be much better if that was possible.

Cheers

[boscoe99]

Yes. It is a flush fitting port.

[Valenciano71]

Yes. It is a flush fitting port.

Mil gracias !! Yo tampoco lo sabía,saludos.

[DennisG01]

Valenciano - just a side note - the muffs will actually do a better job of flushing the engine since you'll run the engine and let it heat up. The flush port is still good, though.