Small Engines (Lawn Mowers, etc.): Mower wont fire, craftsman model, safety switch

Question
Craftsman model 917.2559105, 18hp electric start
After mowing 2 weeks earlier, mower was parked in the barn.
Mower will turn over like normal but no spark. I installed new plugs but still no fire. I put a volt meter on the first plug and had no reading. The second plug bounced between 10 & 11 volts. I figured something wrong with the Ignition cable and the Armature. Any ideals? I hate to tear this all apart and find out that its a safety switch or something.

Answer
Hello Robert:

From your Description it Sounds like a Safety Switch is Causing this Problem. The Coil May be Bad, but I am Sending the Instruction File for Checking the Coil/Ign Module/Magneto in Case the Coil/Ign Module/Magneto is Bad. The Following is an Instruction File I Made for Checking a Coil/Ign Module/Magneto Problem. With the Spark Plug/s Removed, 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/s Fires. If No, then Disconnect the Shut Off Wire at the Control Bracket (if Applicable) 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/Magneto is Bad. The Coil/Ign Module/Magneto to Flywheel Gap is .020in. On Some Model JD Engines, there is a Igniter that Goes Bad and Not the Coil. The Igniter is the Same as an Ignition Module. If the Plug/s 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 or Clutch 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 and Blade Safety Prevents the Starter from Engaging so the Mower Does Not Move and the Blades will Not Engage 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. The Following is an Instruction File for the Safety Switch System. Any Input is Appreciated. The Color Code of the Wires May be Different than those I Use as a Reference in the Instruction File. **PLEASE REMEMBER THAT THE INSTRUCTIONS FOR CHECKING THE SAFETY SWITCHES IS JUST THAT!!! FOR CHECKING ONLY. I NEVER Suggest a Mower be Operated with a Safety Device or Switch Disconnected or Bypassed. Now. On Some Model Mowers you can Simply Unplug the Safety Switch from the Harness. On Other Models you have to Place a Jumper Wire Between the Harness Terminals (on the 4 Post Switch (Clutch/Brake) Jumper from Same Color Wire white to White First and then Check for Fire, Now Include the Black to Black Wires if No Fire. Check the Clutch/Brake and the Blade/PTO Safety Switches First. Check the Seat Safety Last. Usually the Seat Safety is Not in the System for Starting the Engine. Just to Ensure Someone is in the Seat when Engaging the Transaxle and/or Blades. Use a Paper Clip or a Short Wire to Make a Jumper.** If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. 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 8pm EST (US). My New Day Starts then. Thanks.

Respectfully

John