Weed Eater One

My Weedeater One's Friction pulley broke on the upper shaft where it attaches to the engine. This should never happen. When i engaged the mower the crankshaft spun inside the pulley. After I removed the engine I found the pulley had split at the upper shaft. I ordered the partsbut my question is the crankshaft has a keyway notch on the shaft apparantly to keep the pulley from moving on the shaft.There is a bolt on the bottom of the pulley that bolts to the crank. I cannot find the keyway anywhere online. Does anyone know if the key is used on this pulley or is the pulley locked to the crank by the bolt??