Help with Hoover TV630 dryer please?

I've had my dryer for about 6 years, and it has recently developed a temperamental glitch when I try to start it. This problem is getting worse, and necessitates greater patience and perseverance as time goes on. Once working the appliance seems fine, and completes the cycle without further problem. I am guessing that a contact is worn somewhere, but having taken it apart I have been unable to identify the problem? Any ideas?