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Clark's Garage944 · 924 · 968 · Turbo
Cooling System

944 Cooling System

Overview of the 944 cooling system flow path, including thermostat operation at 83 °C and vacuum-controlled heater core flow.

Difficulty: Easy1 min readApplies to: 944 · 944S · 944S2
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The 944 cooling system bypasses the radiator until the coolant temperature reaches 83 °C181 °F, at which point the thermostat opens. After the thermostat opens, coolant is circulated through the radiator and back to the suction of the water pump.

Flow through the heater core is controlled by a vacuum-operated diaphragm valve that fails open on loss of vacuum. Vacuum is supplied to the valve operator via a vacuum solenoid in the HVAC system.

Tags:cooling systemthermostatheater coreflow diagram

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