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Hydraulic Flow








N POSITION
As the engine turns, the ATF pump also starts to operate. Automatic transmission fluid (ATF) is drawn from (99)and discharged into (1). Then, ATF pressure is controlled by the regulator valve and becomes line pressure (1). The torque converter inlet pressure (92) enters (94) of torque converter through the orifice and discharges into (90). The torque converter check valve prevents the torque converter pressure from rising. Under this condition, the hydraulic pressure is not applied to the clutches.





1 POSITION
The line pressure (1) becomes the line pressure (4) and 1st-hold clutch pressure (16) as it passes through the manual valve. Also, the line pressure (1) goes to the governor valve and becomes the governor pressure (60). The governor pressure (60) is supplied to the 1-2 and 2-3 shift valves. The shift valves remain on the right side because the governor pressure is lower than the valve spring tension. The line pressure (4) becomes the 1st clutch pressure (10) via the orifice, then goes to the 1st clutch. The 1st clutch pressure (10) is also supplied to the servo control valve and 2-1 timing valve to move them.to the left side. The 1st-hold clutch pressure (16) goes to the 1st-hold clutch via the 1-2 shift valve, orifice and 4th exhaust valve. In the 1 position, the 1st clutch and 1st-hold clutch are engaged. The line pressure (4) also goes to the servo valve via the servo control valve, and holds on the servo valve in the driving range.

NOTE: When used, "left" and "right" indicates direction on the hydraulic circuit.





2 POSITION
The line pressure (1) becomes the line pressure (2), (4), (4'), (25) as it passes through the manual valve. Also, the line pressure (1) goes to the governor valve and becomes the governor pressure (60). The governor pressure (60) is supplied to the 1-2 and 2-3 shift valves, but the 1-2 and 2-3 shift valves remain on the right side. The line pressure (25) goes to the 2-3 shift valve via the 1-2 shift valve and becomes the 2nd clutch pressure (21). The 2nd clutch pressure (21) becomes the 2nd clutch pressure (20) as it passes through the orifice, then goes to the 2nd clutch. The line pressure (4) becomes the 1st clutch pressure (10) and flows to the 1st clutch, servo control valve and 2-1 timing valve. The line pressure (4') also holds on the servo valve in the driving range. In the 2position, the 1st clutch and 2nd clutch are engaged. However, no power from the 1st clutch is transmitted because of the one-way clutch.

NOTE: When used, "left" and "right" indicates direction on the hydraulic circuit.

D4 OR D3 POSITION





1. 1st Gear: The flow of fluid through the torque converter is the same as in the E] position. The line pressure (1) becomes the line pressure (4).The line pressure (4) becomes the 1st clutch pressure (10) as it passes through the orifice. The 1st clutch pressure (10) is supplied to the 1st clutch and 1st accumulator, consequently the vehicle will move as the engine power is transmitted. The line pressure (1) becomes the governor pressure (60) by the governor valve and travels to each shift valve. But, all shift valves remain on the right side because the governor pressure (60) is lower than the shift valve spring tension. The line pressure (1) also flows to the modulator valve and throttle valve B. In the D4 or D3 position, the line pressure (4') flows to the servo valve and holds it on in the driving range as in the position.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.





2. 2nd Gear: The flow of fluid up to the 1-2 and 2-3 ship valves is the same as the 1st gear. As the speed of the vehicle reaches the prescribed value, the 1-2 shim valve is moved to the left side by the governor pressure (60) and uncovers the port leading to the 2nd clutch; the 2nd clutch is engaged. Fluid flows by way of: Line Pressure (4) -> CPC Valve-Line Pressure (4') -> 1-2 Shift Valve-Line Pressure (5) -> 2-3 Shift Valve-2nd Clutch Pressure (21) -> Orifice-2nd Clutch Pressure (20) -> 2nd Clutch. The 2nd clutch pressure (20) is also supplied to the governor cut valve. The governor cut valve is moved to the left side to cover the port of the governor pressure (60) to the 3-4 ship valve. The hydraulic pressure also flows to the 1st clutch. However, no power is transmitted because of the one-way clutch.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.





3. 3rd gear: The flow of fluid up to the 1-2, 2-3 and 3-4 shin valves is the same as the 2nd gear. As the speed of the vehicle reaches the prescribed value, the 2-3 shim valve is moved to the left side by the governor pressure (60) and uncovers the port leading to the 3rd clutch. Since the 1-2 ship valve is kept on the left side, and the 3-4 shim valve is on the right side to uncover the port leading to the 3rd clutch, the 3rd clutch is engaged. Fluid flows by way of: Line Pressure (4) -> CPC Valve-Line Pressure (4') -> 1-2 Shift Valve-Line Pressure (5) -> 2-3 Shift Valve-3rd Clutch Pressure (31) -> 3-4 Shift Valve-3rd Clutch Pressure (30) -> Orifice -> 3rd Clutch. The hydraulic pressure also flows to the 1st clutch. However, no power is transmitted because of the one-way clutch as in the 2nd gear.

NOTE: When used, "left" and "right" indicates direction on the hydraulic circuit.





4. 4th gear (D4 position): The flow of fluid up to the 1-2, 2-3 and 3-4 shim valves is the same as the 3rd gear. As the speed of the vehicle reaches the prescribed value, the 3-4 shim valve is moved to the left side by the governor pressure (60) and uncovers the port leading to the 4th clutch. Since the 1-2 and 2-3 shim valves are kept on the left side, the fluid flows through to the 4th clutch; the power is transmitted through the 4th clutch. Fluid flows by way of: Line Pressure (4) -> CPC Valve-Line Pressure (4') -> 1-2 Shift Valve-Line Pressure (5) -> 2-3 Shift Valve-3rd Clutch Pressure (31) -> 3-4 Shift Valve-4th Clutch Pressure (41) -> Orifice -> Manual Valve-4th Clutch Pressure (40) -> 4th Clutch. The hydraulic pressure also flows to the 1st clutch. However, no power is transmitted because of the one-way clutch as in the 3rd gear.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.





R POSITION
The flow of fluid through the torque converter circuit is the same as in the R position. The line pressure (1) becomes the line pressure (3) as it passes the manual valve. It then flows through the reverse control valve to the servo valve, causing the reverse shift fork shaft to be moved to the reverse position. The line pressure (3') from the servo valve goes to the manual valve and becomes the 4th clutch pressure (40). Then it goes to the 4th clutch; the power is transmitted through the 4th clutch. When the N position is selected while the vehicle is moving forward at more than a certain speed, the line pressure (3) is cut by the governor pressure (60) which activates the reverse control valve. When shifting to R from D4, D3, 2 or 1 position, the servo control valve is moved to the left side by 1st clutch pressure (10). The servo control valve combines with the reverse shift fork shaft detent system to control movement of the servo valve.

NOTE: When used, "left" and "right" indicates direction on the hydraulic circuit.





P POSITION
The flow of fluid through the torque converter circuit is the same as in the N Position. The line pressure (1) becomes the line pressure (3) as it passes the manual valve. The line pressure (3) flows through the the reverse control valve to the servo valve, causing the reverse shift fork to be moved to the reverse position as in the R position. However, the hydraulic pressure is not supplied to the clutches. The power is not transmitted.

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