1967 Hedlight Switch

[Rick S.]

I checked the archives for a problem I am having with the headlight switch and was unable to locate an answer. The problem I am having is that the instrument/cluster lights only work when the switch is turned to the brightest position. When I try to turn them down to dimmer, they go out entirely. Also when turning the switch to turn the under dash lights on with the doors closed, the interior lights do not come on. I presume that the rheostat in the switch is the culprit, so my question is, is this repairable or just buy a new switch? If a new switch is in order should I look for a NOS 1995149 or buy a newer Delco model?
TIA
Rick

[Joe L.]

Re: 1967 Hedlight Switch

Rick-----

This is a somewhat common problem and it is the rheostat. That's usually the first thing to go in these switches and probably accounts for more replacements than anything else. I've tried to repair these with no success. Perhaps, though, others have and can suggest a repair methodology.

The 64-67 headlight switch is currently known as GM #1995179. It's not exactly the same as far as appearance goes, but it's NEW and 100% functional. By the way, the 64-67 headlight switch is the only 53-82 Corvette headlight switch which remains available from GM----all the others are discontinued. It's "survival" probably has a lot to do with the fact that it has wide application among other 1964-1973 Chevrolet models.

I suppose that one could discern the differences in the original versus the current replacement if one were to peer up under the dash, but I would not let such an eventuality stop me from using the new switch.

[Jack H.]

Agree

Joe's dead nuts on. Symptoms you report are typical of the dimmer rheostat having seen a prior electrical overload and its windings being melted at a particular point. When the potentiameter's wiper is above the break point, things work. When the pot wiper crosses below the open circuit position, she's dead.

It's probably possible to fix an original, but it's not worth the exercise. The pot mechanism is a wire winding embedded in a ceramic whose three lead lines are riveted to their mating connector lines in the switch assy itself. Trying to drill out those rivets and do a 'transplant' is a )((*& of a job. Plus, once you've got a good donor switch to provide the rheostat assy, why not just clean up that switch and use it?

[Michael H.]

Re: 1967 Hedlight Switch

Rick,

As mentioned, the 1995179 will interchange with the original 1995149 but there is one difference in function. Your dash lights may not be quite as bright with the new part. Not exactly sure what changed but since the 179 was originally from some other model Chevrolet/GM, I suppose the rheostat may be limiting the current flow for a model with less requirements. I first noticed this when I replaced the original switch in my 66 20 years ago. I even replaced it again thinking I had a defective new part. Same problem. My original switch lost just part of the rheostat so I reinstalled it. They work perfectly on full bright but there's a dead spot in the middle of the range. Maybe Jack Humphrey, our electronics guy, can explain why this happens.

[Peter L.]

Re: Headlight Switch

Michael - I've seen the midsection of the rheostat wire come loose from the ceramic and the result was that the wiper contacted the rheostat wire at the beginning and at the end and no instrument lights in between. Couldn't see any way to repair it short of buying a new one. Probably one of the Corvette light switched made by Lucas, The Prince. Pete

[Michael H.]

Re: Headlight Switch

Peter,

I always wondered if a new one could be grafted over an old correct plate? Never really looked at one to see if this would be possible. I'll look at an old switch in the AM.

[Rick S.]

Re: 1967 Headlight Switch

Thanks to all for your help, I will get a new switch.
Rick