Small Engines (Lawn Mowers, etc.): Briggs and Stratton 19.5, briggs and stratton, spark plug wire

Question
I have a Craftsman mower 917.270913. It has a Briggs and Stratton 19.5 I/C Platinum engine. I had been mowing for about 25 minutes and turned the key off to take a break. It backfired once before it died. A few minutes later I filled it up with gas (it had used about half a tank) and tried to start it again. The engine would spin but, it wouldn’t start. I pulled a spark plug wire off and wasn’t getting any spark.

I went to ask a friend for help. 45 minutes later, we put the spark plug wire back on… it started up and I finished mowing. It backfired again when I turned it off.

Since that time, starting has been sporadic. Every time it wouldn’t start, there was no fire to the spark plug. I ordered a new coil from Sears and installed it. It still wouldn’t start and got flooded. I bought new spark plugs and it started up like new. I killed it and we couldn’t get it to start again that day.

The next morning it started up and ran fine until we killed it and it hasn’t started since.

Any help???


Answer
I think the 1st place I would look would be the flywheel key it could have sheared when the engine backfire putting it out of time.  The next place I would look would be ground wires for the ignition circuit.  The next place would be a safety switch that has come out of adjustment.  Be sure all of your connections are clean and tight.