Got a bit of a problem on my truck. Need a replacement part and don’t know what it is called. Early 70’s Ford 302 V8. The engine intake air temperature is regulated by a vacuum motor which controls a flap in the air cleaner ass’y. The flap opens and closes to adjust the proportion of cold and air heated by the exhaust manifold. It’s done to reduce emissions on cold starts and make the engine warm up faster. The vacuum source comes directly from the intake manifold, and the hose goes to a small “unknown-named gadget” (UKG) on the underside of the air cleaner, and from there another hose to the flap-controlling vacuum motor itself. That UKG is what I need.
I’ve always thought the UKG was just a pass-through, and the vacuum motor itself had a temperature sensor. But looking at the UKG, I can see that it is some kind of bi-metal strip and is probably what regulates the amount of vacuum to the vacuum motor. Anyway, that UKG is leaking vacuum for some reason and causing a lean idle mixture and poor idling.
Anybody know what the UKG is called? If I can’t source a replacement, do you think it is fixable? Any ideas for a work-a-round?
This is what the vacuum motor looks like
This is sort of what the unknown named gadget looks like