Small Engines (Lawn Mowers, etc.): Simplicity rider possessed, auto repair shop, spec numbers

Question
I have a 2 year old Simplicity ZT 1644 with a 16 hp Kohler engine. I used the mower Sunday with no issues at all. Went back out to mow tonight (Wed.) and when I hit the key it fired right up but died almost immediately. I hit the key again and nothing! I lifted the cover and checked the cables at the battery which were tight when I heard a click from the solenoid. I realized that I has left the key in the run position. I closed the cover and heard the click again. Climbed on and turned key to the start position and again nothing. I left the key in the run position and just sat there. Now here is the weird part, about ever 25-40 seconds the solenoid clicks. I cant tell you this is normal or not cuz I am not in the habit of leaving the key in the run position without the engine running. If I hold the key securely in the start position at about the same 25-40 seconds it will engage the starter and even try to fire momentarily but dies right away. I checked and charged the battery, pulled the wires from the ignition switch and cleaned the connections with electric contact cleaner. Still no luck. I am fairly certain it is electrical, like something is overheating, maybe a relay? I am a auto repair shop owner but I have NO small engine experience at all. Any help would be appreciated

Answer
Hello Curt:

From your Description, this May be the Safety Interlock Relay (if there is one) Causing the Problem. Send me the Model and Type or Spec Numbers Off the Engine or the Mower Model Numbers, Please. With these I can Locate the Proper Manual and Better Assist you. The Engine Model Numbers May be Stamped Into the Blower Housing (metal engine cover) Above the Spark Plug and the Mower Model Numbers May be Located Under the Seat on the Body of the Mower. Thanks.

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