My recently acquired Murray riding mower starts fine, but it does not turn off when I turn off the key and the safety equipment (seat kill switch) has apparently been disabled. I reconnected the wires under the seat, but I can walk away from the mower and it will idle forever. To get it to shut down I have to pull the plug wire. Can someone direct me to a wiring diagram and/or provide any insight about why this is happening?

Thanks.

Since the previous owner has done some obvious wiring changes there is no way for me to tell you how to undo what I don't know he did, does that make sense? I suspect he has disconnected the wire from the safety switches to the igniton coil which is normally shorted when your trip a safety switch. If you can see what he did you may need to replace the harness.

Can you tell me what color wire the kill circuit has? Or where I can find a wiring diagram for this model equipped with a Tecumseh engine?

Or, can you tell me how the ignition works? By that I mean does the ignition shut off the engine by grounding out the electrical system, like a kill switch on a motor cycle, or by breaking the electrical circuit, like a car?

Thanks.

It is normally a small wire and it operates like a kill switch on a cycle.

Had a Murray that was doing the same thing. Had removed it from winter storage,(outside shed)replaced the oil and started it up. Ran OK, but when I turned the key to OFF, it kept going, even with me off the seat. Checked all the kill circuit switches and the ignition switch. They were all good. I pulled the shroud off the engine and found the kill wire that is connected to the ignition coil had been eaten through by field mice! This wire shorts the coil to chassis ground to kill the spark. With this wire broken the engine won't stop until it runs out of gas. Replaced the wire and all was good.

The kill wire should go in on the right side of the motor , it could be yellow or black .depending on which engine is on it.
Luck