How to Work on Your Garage Idler Pulley. Tip Top Garage Doors provides garage door repair in Raleigh, North Carolina. Work on the idler pulley. Assemble the slider unit and position it well onto the rail. Pick the idler pulley and fasten it on the opposite side of the rail. Contact us for garage door repair services in Raleigh NC. #Raleigh #GarageDoorSupplier #TipTopGarageDoors