Originally Posted by mowerking

i think the more often the better, i use a pressure washer but hold it a little way away as the paint on mowers it not the best and you dont want to blow the paint of. even just use a hose pipe with you finger over half the end to get a powerful jet.
Little tip if your cleaning a pedestrian mower and need to turn it on its side, never turn it so the exhaust is down as you well fill the exhaust with oil, turn it the other side (usually petrol tank way) before doing this take petrol cap off and cover filler hole with bit of plastic then screw lid back on over plastic. (this stops fuel leaking out of breather hole in lid)