Timecutter stalling out while mowing with blades running

Toro MX 4200 Zero turn, after running blades for a while engine will die, if I quickly disengage the blades engine  will keep running, I tried Bypassing the seat safety switch and put in a new pto switch( and spark plugs, fuel filter, air filter and blade belt).. Also I think the clutch has been going out for a few weeks now because when i disengage the blades it takes abt 30 seconds for blades to slow down and another 1- 2 mins to stop spinning, Engine will start right back up after it dies..  and sometimes when i  hit the pto switch blades wont engage.. Could a bad clutch cause engine to die while the blades are running