Sidekick JS 2D 2WD L4-1.6L (1998)
Thermostat: Description and Operation
DESCRIPTION
A wax pellet type thermostat is used in the coolant outlet passage to control the flow of engine coolant, to provide fast engine warm up and to regulate
coolant temperatures.
OPERATION
A wax pellet element is hermetically contained in a metal case, and expands when heated and contracts when cooled. When the pellet is heated and
expands, the metal case pushes down the valve to open it. As the pellet is cooled, the contraction allows the spring to close the valve. Thus, the valve
remains closed while the coolant is cold, preventing circulation of coolant through the radiator. At this point, coolant is allowed to circulate only
throughout the engine to warm it quickly and evenly. As the engine warms, the pellet expands and the thermostat valve opens, permitting coolant to
flow through the radiator. In the top portion of the thermostat, an air bleed valve is provided; this valve is for venting out the gas or air, if any, that is
accumulated in the circuit.
