Classic/Antique Car Repair: Turn Signals, fuse clips, bare wire

Question
Thanks in advance for any help you may offer!  I have a 1977 Corvette, that has recently developed a problem with turn signals.  When I engage the switch, the signal light flashes 8 or nine times very rapidly, then once or twice slowly then stays lit and flashes no more.  I have replaced the flasher and no difference.  I checked the old flasher by swapping it to another vehicle and it worked fine.  I am using the heavy duty flasher.  All lamps light and work fine.  Any thoughts?

Answer
This will take some tracking down.  Does this happen on both sides, or only on one side?  If it is only on one side, you probably have a bad socket ground on that side, either on the front or rear bulb.   

I don't know if the 77 uses a separate bulb for the rear turn signal.  If it shares the rear bulb the brake lights, it is possible that there is a bad ground back there anyway.   

Check both front and rear on that side by taking the lens off and pushing a bare wire end into the socket between the bulb base and the socket, then touching the other end of the wire to some solid ground (I realize this can be a problem on a Corvette, but the bumper should be bolted to the frame, so try that).  If that makes it flash normally, take that socket out and clean the bejabbers out of it, and make sure it's ground wire is in good shape and connected at both ends.  This should cure it.

On the other hand, if it does this on both sides, we have a totally different type of problem.  I suspect a problem in the flasher socket or perhaps in the fuse prongs.  Try running the flasher + lead direct from the battery to see if that makes it flash OK.   If that works, then take the fuse out and clean the bejabbers out of the fuse clips etc.  It is even possible that the fuse is dirty or not makeing good contact internally, so replace that.   The other potential spot for trouble is in the bulkhead connector where the wires go through the firewall.  In this old a car, it is possible that some of the contact are dirty and making poor contact, but I would expect this to show up as a dim bulb in the front turn signal.

Anyway, see if this helps at all, and let me know what you find out.  We'll track it down.   I hope it doesn't lead to the turn signal switch, so lets explore everything else first!

Dick.