[Van Manson]

1967 headlights go on and off by themselves , has anyone had this problem if so what was the cause and solution ?

 

[Seafoam jcode]

1967 headlights go on and off by themselves , has anyone had this problem if so what was the cause and solution ?

I would bet it's the circuit breaker inside your headlight switch that keeps cycling. Your headlights are not fused, because if the fuse blew while you were doing 60 down a mountain road at night, you'd be completely in the dark. The circuit breaker allows the lights to work to some degree without overheating the wires. Are you using halogen headlights? These draw more current than your headlight circuit was originally designed for. I had this same problem on my '85 Mustang after switching to halogen headlights. After going through 3 headlight switches (they would usually last about a year and a half before the flickering would start up again), I built a relay box to take the current load off my headlight switch. You can buy one from Rocketman's Classic Cougar Innovations http://www.rccinnovations.com/index.php?show=menu-hrk-all or build your own like I did.
http://www.mercurycougar.net/forums/showthread.php?28922-Hella-H4-H1&p=234165#post234165

 

[tbm3fan]

Second that. I just finished building three relay systems for the F100, Park Lane and Polara. Even though I won't be putting in halogen lamps this relay system now allows a full 12V to the lamps which are now much brighter than stock. The one from Classic Cougar Innovations looks to be between 14-16 gauge wire. Built my own as I wouldn't settle for less than 12 gauge everywhere. My Cougar hasn't been driven at night in the last 20 years so I may not put one in that car.

 

[doctordesoto]

make sure you fuse the relay system---sounds like a shorted wire or connector