We all do it mrs O.
Back in April I took the lawn mower in to be sharpened and as it had water in the system.
Got it back and decided to cut the green fuzzies and after the first three passes and under a tree it gave up the ghost. Had I run out of petrol? Went and filled it up and pulled the starting rope. No joy. Again and again.
I let it cool and tried again and again, then later on and even next morning. Must be water in the petrol.........so back into the car and back to the service shop, conveniently in our nearest village.
I explained the situation. He takes a look at it - "Your cable to the spark plug is undone..........."
Major Doh.