turn signal/flasher problem

[davidg]

My turn signal/hazard flasher is working erratically. In the morning and shortly after dark(within 1 hour or so) they blink very rapidly, as if a bulb was burned out. The rest of the day they are fine. They seem to make a slow transition from fast blinking to normal in the morning, it takes a couple of hours for them to normalize. At night, within an hour after dark, they go from normal operation to rapid mode(I haven't observed this while driving, only after parking and restarting). I have removed every light bulb from the taillights and front markers, cleaned their contact places, and reinstalled with die-lelectric grease. I observed no sign of corrosion anywhere. I replaced all the fuses in the fuse box with new fuses as well. I washed the car(78 300D)during the day,and the lights worked fine until it got dark. They work fine during daylight hours with the headlights on as well. Is my blinker relay on the way out?thanks for any help