I have an old Metz 402 unit and would like to rebuild it for use. I've had it in storage for about 10 years and when I load a dryfit battery, the power pack makes the traditional "whine" sound but never powers up the flash head. The voltage coming off the power pack cord is reading about .6 volts, and I know from previous testing that it should be about 6.5 volts. My question is, could the power pack problem be the capacitor inside? Is the powwer from the dryfit being stored in this capacitor, and if bad would replacing it only solve the problem?? I also opened the flash head and will be looking for a replacement capacitor fpor that as well. Any info, insight, help would be appreciated.