SSI UNIT QUESTION

I have an old Tecumseh oh180. The SSI went out on it. I had one from a Tec HH120 and put it on the tractor. My starter failed and I replaced it with a new one which spins much faster. The unit worked prior to the new starter. Is it possible that the faster spin is causing the unit to fail. If so, what is the fix?
Thanks

in theory they should work from the 12 to the 18. Did you go back over all the wiring and make sure everything is good? Make sure the wire coming from under flywheel to SSI unit is hookedup preperly and not grounded out. I suggest unplugging the clip that comes form the motor up to the regulator. It contains the kill wire, see if you have spark once it's unplugged. If so, your switch most likely developed a short somehow.