I did my fuel filter recently for the first time.Yes,my clamp was also broken by the previous owner/garage! This sounds paranoid but many years experience teaches that with filters especially with oil filters and if working at the week end, check you've been sold the right one and the dimensions are the same. When I changed my filter I replaced those pinch type hose clips with new tight little jubilee clips for extra peace of mind. Finally, before you offer up the new filter, prime it with fuel first then fit it.This should help to reduce the possibility of air getting in to the system.I didn't do this because the manual didn't mention it and well, you know....so when I couldn't start the damn thing after nigh on an hour I had to take off the engine cover [1.9 Tdi], loosen [not remove] the fuel injector unions and give it a damn good pull on the ignition. I would advise care if you have to do this as some fuel will spray up and it should not come into skin contact etc. Replace the unions carefully to avoid ingress of dirt etc. A friend of mine also told me never to replace a fuel filter such as this whilst parked on a slope. I don't know if this is the best way of purging air from the system but it worked for me that day.