I HAVE AN OLDER MODEL HUSQVARNA MODEL LTH130J. IT WAS USED WHEN I BOUGHT IT BUT IS OR WAS VERY FATHFULL. MY PROBLEM WITH THE MOWER NOW IS WHEN I PULL UP ON THE SWITCH TO ENGAGE THE BLADES, THE BLADES DON'T MOVE, BUT SOMETIMES THEY DO MOVE, BUT NOT FOR LONG, AND THEN THEY STOP MOVING AGAIN. I...