Starter Stays Engaded Even With Ignition Off

Sorry, I posted this in the wrong section so I copied and pasted this here.

I'm currently dealing with a starter/starter solenoid issue with my dad's lawn mower. It is a 13hp John Deere LT133 with a Kohler engine. Nearly every time I start the mower, the starter stays engaged even when I turn the key to the off position. Even if the engine starts, it stays engaged. It does not make any grinding noises or anything, but the solenoid stays engaged so that the gear moves up and contacts the flywheel. You can also hear the starter motor whirring as it normally would. The only way I can get it to disengage and shut off is to release the clutch. Also, if the engine starts and I turn the key off, the engine will shut off, but the starter will still be going. It obviously stops if I disconnect the battery also. Am I just dealing with a wiring issue? Is there a switch on the clutch that is connected to the ignition switch somehow or is it all mechanical? I just removed the entire wiring assembly for inspection and the ignition switch looks horrible. I'm going to clean the contacts and maybe even try to disassemble the switch to clean the internal contacts as well. Any suggestions in the meantime?

Just replaced the switch, or as suggested on your other post replace the solenoid. Better yet test each to find out which one is bad. Please never do identical threads in two different forums, it will only confuse you and those who will try to help.

Rivets said:

Better yet test each to find out which one is bad.

Click to expand...

This is a lot better suggestion then just start replacing parts. Just buy a cheap test light.

Apart from wiring the starter or solenoid wrong or a faulty solenoid there is no way for the starter to remain engaged when the ignition is turned off.
So the first thing to do is check that the solenoid is working properly.
There should be no continuity between the top 2 big poles except when the small wire at the bottom is getting 12 V.
A photo of you solenoid would be a great help.
I did go to a customer who had replaced their solenoid that had a small ground wire that went from the mounting bolt to a ground tab on the solenoid.
The connected this to the hot lead on the top thus energising the solenoid so it never turned off till it burned out.