The car (92 900s) was cranking but not starting, so I pulled the rotor and took it in to the parts store. I was told it looked worn and (the rotor arm?) was bent. I bought a new one and a distributor cap. The rotor was not going on so I gently tapped it. Apparently I tapped it with enough force to break it. Is it usually difficult to get the rotor on? BTW, I know there is only one way it goes.