You should avoid tipping your petrol lawn mower onto its side as this may cause fuel or oil to leak into the air filters. If this happens then your mower may begin to smoke or you may find you have difficulty getting it to start up. If you need to tip the mower over to perform maintenance on the blades, for example, you should ensure that it is completely empty of any liquids. Tilting the mower backwards to access the underneath of the deck is also an option, but sometimes doesn’t provide enough clearance.