Air Cleaner - Thermostatic: Operation

1986 Toyota Pickup Base, 22-RTE, R151FSECTION Operation

When intake air temperature is low, vacuum valve is closed. Intake manifold vacuum will act on heated air door diaphragm. This causes diaphragm to pull up and close cool air intake. As intake air temperature rises, thermal valve opens, allowing cool air intake door to drop and allow unheated air into air cleaner.

Fig 1: Hot Air Intake System (HIC Valve-Type Shown; Thermal Valve Type Similar)
G38374Courtesy of Β© TOYOTA, LICENSE AGREEMENT TMS1002
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