Hd6g starting problems

If you know how to use a multimeter, place on terminal lead end on the smaller terminal, (trigger, or enable and usually flat) and the other to ground. An infinite resistance indicates an open coil and the solenoid is bad. A resistance reading between 30 and 300 ohms and it is good and someplace else needs evaluated. This needs done with the trigger, or starter enable wire disconnected.

Another thing you can do and I want to stress is make certain that son of a bitch is in neutral first, then with a short length of wire, or screwdriver, short the terminal the battery lead affixes to and the small flat terminal the trigger, or starter enable wire attaches to. This bypasses any safety's involved and if the tractor is not in neutral, it will lurch forward if the starter turns. If the starter still does not operate, you either have a grounding problem from the starting batteries, battery voltage is not being routed to the starter solenoid terminal, or the solenoid is open electrically. If the later, remove all cables and wires from the starter solenoid. With an external 12VDC battery and set of booster cables, connect the positive booster cable end to the threaded stud the tractor battery cable normally attaches to. Attach the negative booster cable end to the starter motor case directly. Jumper, or short the two terminals mentioned earlier to ascertain solenoid condition. If it still does not respond, I would pull the unit from the tractor and send into a rebuild shop for reconditioning. I'm aware your system is a 24VDC system but this is a troubleshooting scenario and 12VDC will work to get a response from the starter. Doesn't have to start, just engage and respond. If you have good batteries in the tractor, you can use them with booster cables interconnected the same way except for 24VDC.

If you still get no response from the starter, you can as a final test jumper with your positive lead to the large threaded stud that enters the starter motor housing and is usually connected to the solenoid by a copper strap. This will bypass the solenoid spinning the motor itself and won't slip the drive into the flywheel ring gear.

Given you mention there is no response from the starter solenoid, I really don't think the starter motor suspect at this writing. No proof but suspect your problem is upstream of the starter motor.

Some of this you've been through already I know. Don't forget, or miss the basics involved.

 

Can't stress enough the importance of clean grounds and terminations. Nature of the beast in electrical work.

I too always have both heavy supply cables running directly to the starter motor and/or assembly itself; #2 at a minimum up to 2/0 dependent upon application.