HELP !!!!! Engine wil not STOP !!!!!

[cobra 53]

Hi folks,
After I started the engine (SPF 302 with MSD 6 ignition box) to drive a little after a longer time, I realized a big problem:
I tried to stop the engine. Turning the ignition key "off", the engine did not stop. Turning the battery cut out switch "off", the engine did not stop. Taking off the two keys, the engine did not stop. All gauges turned to "zero".
I finally stopped the engine using the 5th.
Putting in the keys to start the engine is not a problem, but stopping in an ordinary way with the keys is still not possible.
Do you have any good suggestions???

Thanks, Rico

[Bill D]

You have a run on condition caused by alternator feedback

[cobra 53]

Thanks Bill. Can I find the failure in the alternator itself ?

[Bill D]

Nota failure. The exciter is sending voltage back to the ignition circuit. You need to add a diode to the circuit to prevent this condition