The solenoid has two large cables mounted to it, one from the battery and one going directly to the starter motor. When you turn the key to the
position, a trigger voltage is sent down to the solenoid and the solenoid should connect those two large cables to send battery voltage directly to the starter motor.
There are a couple things to test for. The first you already noted, the contacts in the solenoid are large and you can normally hear them make the connection with a â€œclickâ€ when you turn the key to the
position. The second test is to see if the solenoid is connecting the two large cables. You can do that by removing the cables and checking for continuity across them with an Ohm Meter or Test Light when you turn the key to the
position. The last test is to confirm the trigger voltage is reaching the solenoid when you turn the key. There should be one or two smaller wires going to the solenoid as well as the two large cables. One of those wires should have approximately 12 volts on it when the key is turned to the
position (if you have two wires, the other one will be a ground wire only).
In this case, you are hearing a click which likely indicates the solenoid is getting trigger voltage and is trying to connect the cables so the solenoid itself is likely okay. You can do a quick confirmation if you take a screwdriver with a plastic handle and touch the metal blade across the two mount bolts for the two large cables. Be sure to protect your self and hold the handle of the screwdriver only since there should be battery voltage present that could spark or quickly create heat.
When you manually connect, or â€œjump,â€ these two cable points the starter should begin to spin. If the key is off the tractor will not start but the starter will still spin (since you are manually powering the starter motor).
I am guessing that in your case the tractor will not try to start, since it sounds like you can turn the key and the solenoid engages but nothing else happens. If that is the case there are a couple of things that might commonly be happening. You might have a bad battery or starter cable (one of the two large ones connected to the solenoid) or something may be preventing the starter from turning regardless of input. A quick way to check both is simply to test for power where the one large cable connects directly to the starter. If you have 12 volts or more there when you turn the key to
then everything is working up to that point and the starter has an issue.
It could be a failed starter motor, but often it is something simple like a jammed gear where the starter engages the flywheel to turn the engine over. In that case you can try manually turning the engine to free the jammed gear. Moving the engine output pulley, or even the screen at the blower housing, back-and-forth will often do that.
If you had low, or no, voltage at the starter when you tested and the solenoid tests okay, then one of the two large cables to the solenoid has failed inside or is not making a clean contact at a mount point.
Or, sometimes, a battery can still show good voltage but will short when a load is applied. You could check that quickly by jumping the battery. There is a video link
on that and some other links that might also be helpful and there will also be troubleshooting information in your
that should help.