To know exactly which type of engine stop solenoid configuration you have, your tractor's serial number is important.
The WSM provides different control scenarios determined by serial number.
I will describe the most likely one but there are others especially if your tractor is equipped with OPC or Operator Presence Controller.
The engine stop solenoid will have two internal coils both grounded through the solenoid case.
One coil is strong and is a Pull in coil whose job it is to retract the solenoid plunger during initial starting overcoming any internal friction..
The second coil is much weaker and is designed to hold the solenoid plunger continually retracted once the pull in coil has done its job.
The stronger pull in coil will overheat if powered continuously hence the weaker hold coil which can be powered continuously and not overheat.
You have to test both internal coils independently. Measuring resistance between one connector wire and the case and then the second connector wire and the case is the test. You should measure resistance which is significantly different between the two coils.
From memory the ohm values are approx. 0.375 Ω and 15.6 Ω
Because there are two internal coils and these are powered at different times, you need to investigate the two power supplies to the solenoid. This check can be done with a test light at each solenoid terminal wire having the test light grounded as you first probe one wire and then the other while changing key switch positions.
The pull in coil will be powered in the Key START position. The Hold coil will be powered any time the key is in the ON position and possibly the START position too but I have not checked this.
If what I have described does not seem to match your tractor, please provide the serial number and I will look further.
Dave
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