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Thermostatic Air Cleaner: Description

All Jeep vehicles use a system for pre-heating the air entering the carburetor. This system is part of the air cleaner and maintains air temperature at a point where the carburetor can be calibrated at a leaner setting to reduce hydrocarbon emissions and improve engine performance during warm-up.

Jeep systems are vacuum operated and consist of a heat shroud on the exhaust manifold, a hot air duct, a thermal sensor switch, a vacuum motor, an air valve assembly and a reverse delay valve.

Fig 1: Jeep Thermostatic Air Cleaner Assembly
G09337258Courtesy of CHRYSLER GROUP, LLC