Carburetor: Description and Operation

Fig 2 - Carburetor:

The TQ (Thermo-Quad) carburetor, is unique in design in that it has a black main body or fuel bowl of molded phenolic resin. This acts as an effective heat insulator. Fuel is kept cooler by about 20 degrees Fahrenheit than in carburetors of all metal design. Another reason for the lower operating temperatures is its suspended design metering system. All calibration points with the exception of the idle adjusting screws, are in the upper aluminum casting or air horn and are in effect suspended on cavities in the plastic main body.