The Stovebolt Site Forums The Shop Area Engine Shop The Case of the Weeping Insulator!

Denny, the insulator I had came from a 47-49 model GMC because it still had knee action shocks. A scrap iron hauler was buying gas at one of our stations and I spotted a GMC frame with engine and drive line on the very top of the pile. I recognized it as a GMC because of the Zenith carb. I offered him a little more than scrap. We agreed to unload it on his way back from San Antonio. I was not at our shop when he returned, and the guys at the shop just unloaded it. The carb had disappeared; probably will appear on eBay, but the insulator was still there. The fact that it was necked down caught my curiosity and I checked a couple of my later GMC's. A guy in Washington State wanted it for a multiple carb setup. I didn't photograph it, but he says the one he has is different, which would explain 2 part numbers. I think he is going to post pictures. The discussion never came to a conclusion as to the purpose. I think to save gas is a good theory. We must remember people who drove then were much more conservative then we are. My father, for instance, was born in 1901 and was an adult during the depression. He talked about it being common practice to turn engines off and coast down hills to save gas. Hoof velocity governors were already common to limit rpms. The insulators are necessary because when you turn off an engine too much heat will transfer to the carb and after sitting about 15 minutes, the engine will be difficult to start because the fuel has perculated out of the carb and the engine is flooded. I will take a picture of an insulator with a sleeve that is not necked down.