Small Engines (Lawn Mowers, etc.): John Deere 160 Tractor, john deere 160, transistor ignition

Question
The tractor has performed flawlessly over the years; shut it off last week and now it will crank fine but not fire. It appears there is no spark - shows .6 volts on the wire going to the coil and no spark from coil at spark plug? See wire from coil (not coil wire) running behind starter - is this a transistor ignition? What provides power to the coil that I can check. Got ripped by the local JD dealer last time I needed a repair - would rather fix it myself. Any thoughts?

Answer
Hello Mark:

The Coil Receives No Power. The Magnets Passing the Coil Pickup Make the Energy for the Spark. Both Wires from the Coil are Grounds. One is Grounded All the Time. The Other is the Coil Shut Off Wire and is Grounded when you want to Stop the Plug from Firing. Remove the Spark Plug. Wrap a Wire Around the Threads and Attach the Other End of the Wire to the Engine Block Turn the Engine and See if the Plug Fires. If No, then Disconnect the Shut Off Wire  at the Control Bracket First, Check for Fire at the Plug. If Still No Fire at the Plug; Then Disconnect the Shut Off Wire at the Coil (usually requires removal of the blower housing) and Check for Fire at the Plug. If No Fire at the Plug , then the Coil/Ign Module is Bad. The Coil/Ign Module to Flywheel Gap is .020in. If the Plug Fires at Anytime During these 2 Checks, then a Safety Switch or Wire May be the Problem. Yes the Engine will Turn Even with a Bad Safety Switch. The Blade Safety is Usually the Cause of this. The Starter Turns and The Engine Doesn't Fire is an Indication of a Bad Coil/Ign Module or a Faulty Blade Safety Switch. The Clutch Safety Prevents the Starter from Engaging so the Mower Does Not Move when the Starter Turns the Engine. The Seat Safety is Designed to Stop the Engine if the Blades are Engaged or the Clutch Safety is Not Engaged when you Leave the Seat. You can View a Breakdown/IPL of the Mower at this Site Addy, http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.H... and Enter the Model Numbers and Click Find. Then Select the Sectional File. Then Select the Section of the Mower you Wish to View Online. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John