Carb icing happens when the temperature and the dew point are close. We get it all the time when it is raining or foggy and the truck is cold. Airplanes have carb heat controls, so I thought I would put one in the truck. I made a small box (stove) out of steel that attaches to the exhaust manifold. A zip tube connects the stove to a valve in the air cleaner snorkel. The valve is controlled by a choke control. When the engine runs rough, you pull the carb heat knob, warm air is drawn from the stove into the carb and it smooths out.
