I have a 2009 LT1050 that I can't keep the mower deck belt on. I took it to a repair shop where they replaced all pulleys and spindles plus put a stronger tension spring on and it still wants to throw the belt off. Any suggestions?
That's the experience I've had with idlers . The stronger spring may have actually made the condition worse. Kill the engine with the pto engaged then take a look at the idler position to see if that sheave is parallel with the stationary pulleys .