Anyone know the temp. range for when it is fully wound up and when it fully unwinds?The automatic choke has a bimetallic spring encased in the black round adjustable housing. Because it's bimetallic, it winds up when it's cold, and unwinds when it gets warm. this spring is connected to the same linkage that closes the choke plate and increases the idle speed. The spring can get heated by an electric wire (electric choke) or by a tube that connects to the exhaust manifold.