<!-- from fixya rte -->Start pto kills engin blows fuse - Kohler Cub Cadet LGT 1054 54" 26HP Lawn Tractor - 13WK92AK010

Pull the connector from the back of the PTO switch and the 4 wire connector at engine. Replace fuse. Turn key to run.

Did fuse blow? No, turn key to start and back to run.

Did fuse blow? No, plug in engine connector.

Did fuse blow? Yes, likely shorted regulator or safety miswired.

Plug in PTO switch.

Did fuse blow? Yes, likely safety miswired.

test the seat switch.

you dont bypass you test it then replace if failed and did you test or check fuse

Bad wiring to pto or electric coil in clutch is burn't.

it is not supposed to start unless some one is in the seat
now for your problem, if engaging the cutter deck blows a fuse then check the wiring for a wire that is cut or shorting out on a lever that moves when the cutter is engaged

replace the pto solenoid as it has an internal short causing the fuses to blow.

check for power to the clutch if yes the clutch could be bad or a wire going to it if no power check the safety switches

Most likely there is an internal short in the PTO clutch, but it could also be in the wiring, which is way cheaper to fix! So, with the engine off, get down on the ground, find the PTO clutch (it's between the two pulleys under the motor) and trace the wires that go to it. Look for a worn spot in the insulation anywhere, especially likely where the wires pass through the chassis or if they've touched a belt or other moving part. If you find a wiring problem, just splice in a new wire.
Ok, if you found nothing, then unplug the connector that connects the wires from the PTO. Start the engine, drive around, engage the PTO switch (of course, the blades won't spin). If the PTO fuse does not blow, you've proven the problem is in the PTO clutch and you must replace it ($150 or so, sorry!). If the fuse does blow, that's good news, you just have a short in the wiring or in the PTO switch itself. Disconnect the wires from the switch to differentiate those two possibilities. The PTO switch isn't too expensive either. Good luck! Please rate my solution if helpful.

Sounds like you have a short circuit, either in the PTO clutch, or in the wiring that goes to it. Inspect the wiring for any obvious spots where insulation has rubbed off or burned. Also look at the wiring at the back of the PTO engagement switch for these signs. Before buying an expensive PTO clutch, unplug its connector. Drive around with the PTO switch on (even though the PTO won't activate and the blades won't be engaged). If the fuse doesn't blow, the problem must be within the PTO clutch. If the fuse still blows, it must be in the PTO switch or the wiring from there to the clutch. Use an ohmmeter to trace and find the short. Good luck!

try unplugging the pto, start the mower, then engage the pto switch. If the fuse still blows trouble is somewhere in the mowers wiring if not the ploblem lies in the pto. hope this helps