In a Summary, a torque converter is a fluid coupling that sends torque from the engine to the transmission. It is planted between the engine and transmission, bolted directly to a ‘flex plate’ that is spun by the crankshaft.
Internal combustion engines generates power by burning fuel that forces the pistons to turn the crankshaft located at the bottom of the engine. This rotational force is transferred to the transmission by the fluid pressure inside the torque converter.
Inside of the torque converter cover is a series of propeller-like blades known as the pump. This assembly turns in sync with the engine crankshaft, forcing transmission fluid onto another blade assembly that is called the impeller. This second set of blades is attached to the transmission input shaft. The amount of hydraulic pressure that it creates inside the transmission dictates the gear and ultimately, the speed of the car.
The impeller’s speed is modulated by the engine side of this hydrodynamic circuit ( speed of the pump blades). When the vehicle is stationary, or the driver matches the brakes, the impeller will slow considerably, while the pump continues to spin. This allows the torque converter to operate like the clutch in a manual transmission – it allows the engine to continue running while the vehicle is at a complete stop.
immediately the transmission fluid has been hurled onto the impeller blades, it has to return to the pump in order to maintain the cycle going. Since the fluid is now flowing in a different direction than the pump, it has
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