Now Stu, I think I know you better, ya just knew some body was gonna come along and further define that statement, didn’t you?? I taint pickin’ on ya, just want to make sure the younger members are fully informed in the correct terminology.
A page from the Professional Plastics catalog does a good job of explaining it: Garolit,
http://www.professionalplastics.com...fnbr/101497/sesent/00/Garolite-Phenolics , Phenolic,
http://en.wikipedia.org/wiki/Phenolic_resin , Bakelite,
http://en.wikipedia.org/wiki/Bakelite Basically the spacers that were made by GM were made from a fiber filled Phenolic resin. A more familiar term, which is now also used as a generic term for this thermoset plastic, is Bakelite.
Bakelite usually had a non-woven fiber reinforcement such as paper, linen, canvas, nylon, asbestoses. There were other fillers such as walnut shell and clay sometimes seen in the Bakelite radios of the 30’s and 40’s. This is also the material that we see in electrical insulators and as handles and knobs on cooking utensils. It has no grain and will brake if dropped, struck with a hammer or crushed with an over tightened fastener.
Garolite on the other hand is a trade name for the McMaster Carr line of Phenolic woven laminates. Originally coined Micarta, which was a Westinghouse trade name for their Phenolic resin laminate. This is the material that we see typically see in circuit boards and are often referred to as G-9, G-10, G-11, etc. Garolite can be made with a variety of binders, i.e., Phenolic resin, Melamine resin, Epoxy resin, Polyamide resin, etc. It, on the other hand is very tough can take bending loads and impact without breaking and is flexible to a degree.
Oh yes, the original question, I agree with what the others say, it's simply an insulator and originally was used without a gasket. I was a parts man for Chevy back in the 50’s & 60’s and can confirm that. But the question still remains, why did they ever make the gaskets in the first place. Probably because the insulators and carb bases got scratched up during service and would leak without the gasket. Since we are looking for a thermal break at this point I see no reason why you couldn't use a gasket on top of and under the spacer if you choose to do so. As long as it does not interfere with the operation of the linkage or fuel and vacuum connections and ports. All of the aftermarket gaskets that I have seen have four vacuum slots so no matter how you put the gasket on it won’t block the port.
Picky, picky, picky! Ok, I’m done! Gotta go make breakfast for my “big old wife.”
Denny Graham
Sandwich, IL
