Blades continue spinning when PTO button is pressed

[bertsmobile1]

Generally PTO clutches are hard wired on the power side & the switch makes a ground connection
Originally ground was made through the clutch body and you switched the power side but this proved to be unreliable
So if your coil has a short to ground then it can be energised all the time & the plug will throw a spark when you disconnect it .
Over tightening can also crush bearings so they will not rotate freely .

 

[ILENGINE]

Generally PTO clutches are hard wired on the power side & the switch makes a ground connection
Originally ground was made through the clutch body and you switched the power side but this proved to be unreliable
So if your coil has a short to ground then it can be energised all the time & the plug will throw a spark when you disconnect it .
Over tightening can also crush bearings so they will not rotate freely .

Most of the mowers at least in the US are power side switched. Some of the early clutches were a single wire grounded through the clutch body and had issues with grounds through the crankshaft and would basically arc gouge the crankshaft in the pto bearing area of the engine sump. But I have also worked on ground side clutches but they are few between