Clock and petrol gauge

[Bathtub Tom]

Kia Pride (Festiva I think), '94, 1324cc, 5-door, 5-speed manual.

My clock loses great chunks of time if the car sits there for a few days unused. I've also noticed the fuel gauge reads about a quarter tank higher after the car's done a few miles. It's almost as if the battery's low on volts, until the alternator charges it up, however the starter spins over fine even after a week unused.
Are these common quirks, do I have to live with them, or is there an easy (cheap) cure.

[dahodges]

The fuel gauge reading may be normal. Check/clean the electrical ground on the clock.

[FB71]

have the battery load tested, just to be sure.

however, its sounds as if the fusible links (three small wire loops, just in front of the left [from sitting inside] strut tower) may be starting to corrode. They provide power to the vehicle's electrical system from the battery, while the large cable on the battery feeds the starter directly. Remove the links and clean the contacts, and replace the links with cartridge fuses.