PART ALERT: We recently discovered a change by GM (and part manufacturer CASCO) in their cigarette lighter housing that could cause 1966 and older Corvettes to short out and burn their wiring harness. The change is a small bi-metal element added to the rear of the housing where the power wire connects (see photo). It was added because of the frequent use of the lighter housing to power items like CB radios, coolers, cell phones and the like. If the use is extended, the electrical draw can result in a heat build-up that should cause the bi-metal element to move, short the lighter, and blow the fuse -- the intended purpose. The problem is that 1966 and older Corvettes DO NOT have a fuse for the lighter or circuit. The result of overloading a non-fused lighter with this element is a dead short in the hot side of the harness, potentially resulting in minor to major harness damage.

The fix is very easy; simply remove the bi-metal element in the rear of the housing.

This should also serve as a warning to owners of 1966 and older Corvettes to not use the lighter socket for extended periods of time, as this could cause heat build-up that could damage a wiring harness.

The original GM part number for the lighter housing is 3986869, replaced by 11516142. Virtually every Corvette parts supplier uses this same housing, so any owner of a 1966 or older Corvette should check the housing and remove the bi-metal element if present.

Corvette Central

Photo Link:
[URL=http://imagehost.vendio.com/bin/viewimage.x/00000000/corvettecentral/640housingfade.jpg]

 

I saw the result of this problem at Howard's Corvettes in Mesa, AZ a couple of weeks ago.......burnt up a brand new harness on a 66 convertible! Everyone please check yours if you have replaced from the original at some point!!!

 

read this after burning up my harness . Would have been nice if Corvette Central would have a note on this . Thanks

 

I believe I read this 7-8 years ago on VH's. I think John Hinckley may have posted it?

 

Surely they are not still selling this part as described. That OP is ten years old.

 

They're still selling it, but there's a warning: "Corvette Central suggests for safety reasons it is a good idea to add a fusable link to your cigarette lighter on pre 1967 Corvettes to prevent overheating of the lighter."

The first of the pictures listed is also a scan of the OP with all the text and images.

 

Here's the "Tech Bench" column I wrote about this issue back in 2008 or so.

 

Ok, now I know why I blew the fuse in my 59. Thank god for Frank the Finks suggestion years ago to fuse that circuit.