[5 Cub Cadets]

Got a 1450 rolling chassis, that I reworked this past winter, putting a 12 hp
engine from a 1200 on it ( so guess, it could now be a 1250, with hydraulic lift?). Put the mule drive from the 1200 on it also, along with the 44A mower deck. Runs good, lifts the deck, but when the electric PTO is engaged, the belt tension release lever pulsates in and out (a couple inches) of the front lower panel. Belt is adjusted to the first V notch on the belt tension release lever, I'm out of tension adjust nut thread. Wrong belt, weak tension spring?? Idea's please.

Thanks,
Dick - 5 Cub Cadets