Electrical issue 67 Coupe

[Lawrence S.]

When I turn my lights on I smell wire insulation (I think) burning after about 5 minutes. Turn the lights off no more smell. I had the instrument panel fuse blow a few times recently. I am curious if there is a ground somewhere I can check and clean to perhaps help this situation, or would one of the lights bulbs that illuminate the dash be causing this because it would not be grounded good in the cluster frame? I don't recall if the cluster frame grounds the bulb to make it illuminate or not? Any ideas?

Thanks

Lawrence

[Edward D.]

Re: Electrical issue 67 Coupe

If the cluster ground was bad none of the cluster illumination light would work. Main cluster ground connector is found near the top of the cluster just inboard of center. You problem is likely the light switch itself. There is a rheostat coil on the front of it for dimming the cluster and these go bad and either don't work or burn. Fix is to replace the headlight switch. Do it before you burn up the wiring. If you smell burning wire or see smoke you have a power short to ground issue heating up the wires. This most commonly happens at the headlight switch or the ignition switch.

[Joe L.]

Re: Electrical issue 67 Coupe

Lawrence and Edward------


Yes, and you can still get a new headlight switch from GM. The current GM part number is GM #19245093 , aka ACDelco D1588. These can be had for about $20-30.

You can also pretty easily find NOS examples on eBay under GM #1995179. They usually range in price from about $50-150. The original switch was GM #1995131 but this was discontinued and replaced in April, 1967 so it's a lot harder to find. Later 1967 may have used GM #1995149 which was discontinued and replaced in August,1968 by GM #1995164. The latter was discontinued in June, 1971 and replaced by the aforementioned GM #1995179.

[Lawrence S.]

Re: Electrical issue 67 Coupe

Guys, I have replaced the light switch with a parts store model.

[Joe L.]

Re: Electrical issue 67 Coupe

Guys, I have replaced the light switch with a parts store model.

Lawrence------

Do you still have the box that the switch was supplied in? If so, what is the manufacturer?

[Lawrence S.]

Re: Electrical issue 67 Coupe

Joe,

It is from Auto Zone, Duralast. Made in Taiwan .

I still have my original. As I recall just the cluster dimmer would not work. May stick that in to see if I have the same issue

[Lawrence S.]

Re: Electrical issue 67 Coupe

Got my AC Delco part number D1588 today. Will install tomorrow hopefully a bad switch is my problem, but this part is also made in Taiwan! Will let you guys know.

[Edward D.]

Re: Electrical issue 67 Coupe

Lawrence,
Did you say the dimmer function did not work on the replacement switch? If no dash lights at all with a new switch you either have a bad contact or a burned wire. Clean the all connector contacts really well when you replace the switch again. Dimming is accomplished by the rheostat coil and contact at the front of the switch; its these that typically go bad and can also cause overheating problems resulting in burned wires.

Joe,

It is from Auto Zone, Duralast. Made in Taiwan .

I still have my original. As I recall just the cluster dimmer would not work. May stick that in to see if I have the same issue

[Lawrence S.]

Re: Electrical issue 67 Coupe

No my dimmer switch works and the cluster lights dim as they should. Its just after a few minutes of the light switch pulled out I smell a burning smell. I can't say for sure it is wire insulation or maybe the rheostat burning? Will change it out in the morning.

[Joe L.]

Re: Electrical issue 67 Coupe

Got my AC Delco part number D1588 today. Will install tomorrow hopefully a bad switch is my problem, but this part is also made in Taiwan! Will let you guys know.

Lawrence-------


Please carefully compare the Auto Zone switch with the Delco. Check to see if they appear EXACTLY the same in every way. If so, then the manufacturer of both is likely the same.

[Lawrence S.]

Re: Electrical issue 67 Coupe

The new AC Delco light switch was very similar but there were differences. The center of the switch that turned and part of the rheostat was very loose as compared to the delco part. There was a rivet difference in one of the fasteners. The delco part dimmer switch operates more smoothly and felt like it was better quality. Very little physical difference however.