The regulator valve maintains constant hydraulic pressure from the ATF pump to
the hydraulic control system. While also furnishing fluid to the lubrication system
and the torque converter. Fluid from the ATF pump flows through B and B'. Fluid
entering from B flows through the valve orifice to the A cavity. This pressure of the
A cavity pushes the regulator valve toward the spring, and this movement of the
regulator valve uncovers the fluid port to the torque converter and the relief valve.
The fluid flows out to the torque converter and the relief valve, and the regulator
valve returns under spring force. According to the level of the hydraulic pressure
through B, the position of the regulator valve changes, and the amount of fluid from
B' through the torque converter changes. This operation is continued, maintaining
the line pressure.
Fig. 36: Regulator Valve Operation Diagram
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Increases in hydraulic pressure according to torque are regulated by the regulator
valve using stator torque reaction. The stator shaft is splined to the stator in the
torque converter, and its arm end contacts the regulator spring cap. When the
vehicle is accelerating or climbing (torque converter range), stator torque reaction
acts on the stator shaft, and the stator arm pushes the regulator spring cap in the
direction of the arrow in proportion to the reaction. The stator reaction spring
compresses, and the regulator valve moves to increase the line pressure which is
regulated by the regulator valve. The line pressure reaches its maximum when the
stator torque reaction reaches its maximum.
2008 Honda Civic LX
2006-08 TRANSMISSION Automatic Transmission - Civic (Except Hybrid)