[jdhoup]

Older Bunton with electrical problems. No crank & no blade clutch engagement. Before even without the engine running, the blade clutch would lock in. (engine wouldn't crank until clutch deenergized).
Now I have 12vdc on both wires to the blade clutch. When I turn the ign switch on I have 12vdc on the proper terminals but also 12vdc on the switch ground. Any thoughts?
Thanks, John

 

[Mark / Ohio]

What is your model number? Maybe one of us can find an electrical diagram for it. Could be the switch itself. But I would also look for any wires connected to the chassis and make sure they are making good connection, maybe even go so far as to remove, clean and reconnect them.

 

[jdhoup]

What is your model number? Maybe one of us can find an electrical diagram for it. Could be the switch itself. But I would also look for any wires connected to the chassis and make sure they are making good connection, maybe even go so far as to remove, clean and reconnect them.

Thanks for your reply. I have attached a copy of the print. Only wire attached to the chassis is the battery ground cable. Note that the lift solenoid works so power is good to the ignition switch.

 

[Mark / Ohio]

That 12 Volts on the ground terminal of the ignition switch is definitely big clue. The question is where does that ground lug on the switch get it's ground? By the way they shade the ground terminal out to the case of the ignition switch in the picture I'm thinking the ground is the case of the switch and it's connection to the body of the tractor. The switch is still installed in the tractor with the lock washer and nut tightened down good, correct?

Looks like the lift solenoid has it's own ground wire to the chassis which could explain how it's still working proper.

One thing I'm curious about is the "TEST SW"? Is that to test the safety shutdown operation?

 

[jdhoup]

That 12 Volts on the ground terminal of the ignition switch is definitely big clue. The question is where does that ground lug on the switch get it's ground? By the way they shade the ground terminal out to the case of the ignition switch in the picture I'm thinking the ground is the case of the switch and it's connection to the body of the tractor. The switch is still installed in the tractor with the lock washer and nut tightened down good, correct?

Looks like the lift solenoid has it's own ground wire to the chassis which could explain how it's still working proper.

One thing I'm curious about is the "TEST SW"? Is that to test the safety shutdown operation?

 

[Freddie521]

12 volts on both leads indicates it's not getting a ground. Some circuits supply the positive to operate with a hard ground, others will supply the ground to operate with a hard wired positive.

 

[Mark / Ohio]

John, your reply has my quote but nothing else?