Starter will not engage. All safety switches are engaged. Jumper selenoid, starter engages, engine turns, but will not start. No fire to magneto when I do this./ Thanks, Louis

check the safety swich on the foot pedal and the cutter engagement if its a manual engagement lever

Not enough information to answer. Need manufacturer, year, model, engine size, 2WD/4WD/AWD, and Manual or Automatic transmission as applicable in order to answer the question.

At the starter relay, you have two red or purple wires, one goes to the starter and the other comes from a 30amp fuseable link. Is that fuseable link circuit hot ?
From the key switch, power goes thru the alarm relay, then the clutch safety switch or automatic selector switch, then to the starter relay. The fourth wire on the starter relay is a ground.
You should be able to put power to the starter relay on the white or yellow wire coming from the safety switch to make the relay engage.
My guess is something wrong with the alarm system.

To check the starter: key off, transmission in park or neutral, brake set. Pull off the small wire to starter solenoid. Then use a small jumper wire from battery cable post on the starter to the solenoid terminal (can also use a small screwdriver to bridge those terminals). Starter motor should engage the flywheel and spin the engine. If nothing, starter motor or solenoid is bad. If starter works, check for power on the small solenoid wire, with key held in crank. Wire should have power, if not, check start circuit from ignition switch to solenoid-the neutral safety switch is in that circuit.

Is the starter actually turning the engine over (engaging), or is it just whirring rapidly? If it is not engaging, then the vehicle certainly will not start. If it is not engaging, there is most likely a shimming issue to be addressed to get the starter to engage. If it is engaging, check carefully the large nut in the starter solenoid. There are usually more than one wire attached to this nut. Ensure that you have not missed replacing any of the wires that came off the starter studs. Some feed back to the fuse paqnel and can be critical for operation.

Beat on the starter with a hammer while someone tries to crank....if if cranks, you need a new starter selenoid. You can also bypass the selenoid by jump starting it with a screw drive to conduct much current between the two bolts on the starter selenoid. Be careful not to touch, unless your full of ****.

The transmission range sensor , park neutral safety switch . Is fuse #23 60 amp in the engine bay fuse block good ?

The problem you describe is consistant with a faulty starter selenoid. You can check the selenoid by attempting to jump power from the incoming hot selenoid connection to the hot that goes from the selenoid to the starter. Do this with the switch in the "on" postion. If the starter then works, replace the selenoid. Good Luck! I hope you find this to be very helpful!

A safety switch may be preventing startup. Jumper out safety switches and see if it starts.

Hello B-N-L:

>>I Suggest you Check the Ign Module First and then the Safety Switches if the Ign Module (Coil) is Good. Remember that the Ign Module May Check Good, but if the Safety Switches Check Good, then Most likely the Coil is in the Early Stages of Breaking Down and will Cause this Problem.
>>You can Check the Ign Module (Coil) by Using the Following Instruction File.
The Following is an Instruction File I Made for Checking and Repairing this Problem.
>>Run the Engine Until it Quits, then 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.
>>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 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 Seat Safety Safety Switch. Usually if the Engine will Not Turn with the Ign Switch; the Blade Safety or Neutral/Clutch Safety Switch 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 Blade and Clutch Safety Switches Prevent the Starter from Engaging so the Blades or 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.
>>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 (Example: 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.**
>>Use a Volt/OHM/Continuity Meter and Check the Continuity of the Switch. The Meter should Show when the Contacts are Closed and Open. The Meter will Swing All the Way Over when the Switch Contacts are Closed and Swing Back to the Rest Point when the Switch Contacts are Open.
>>If the Safety Switches Check Good, then Check the Ign Module (Coil).
>>Thanks.

Respectfully

John