Converter-In Circuit

and the intermediate-high shift plug. This produces

b. Converter-In Circuit (yellow--fig. 2-4).

an upward force at each plug. These plugs and the

(1) The converter-in circuit functions as

intermediate-high shift valve are prevented from

described in paragraph 2-14b, except for two

rising by spring pressure, inhibitor pressure, and

conditions shown in figure 2-4 which differ from

throttle (T) pressure opposing their movement.

those shown in figure 2-3. In lockup operation, the

flow of oil to converter-in line must pass through

e. Low-Range Clutch Circuit (red, black--fig.

2-4). The low-range clutch circuit directs oil to the

the orifice near the left side of the lockup valve.

low-range clutch when the low-intermediate shift

Also, the converter-in regulator valve is shown in an

valve is downward. When the shift valve is upward,

open position, allowing excess oil to return to the

the low-range clutch exhausts through a port at the

transmission sump.

right side of the low-intermediate shift valve bore.

(2) In lockup operation, the torque converter

does not require a flow of oil as great as that

f. Throttle Valve (TV) Circuit (blue, yellow--fig.

required during converter operation, hence the oil is

2-4).

directed through an orifice. When the flow to the

(1) Throttle valve (TV) pressure originates at

the throttle regulator valve when the throttle is

converter is reduced, the converter-in regulator

initially opened. It increases as the throttle is

valve may open to discharge excess oil and limit the

opened farther. This pressure is directed to areas

pressure in the converter-in circuit.

c. Front Governor (Gl) Circuit (blue, black--

near the upper ends of the low-intermediate and

intermediate-high shift valves, to the main

fig. 2-4).

pressure modulating plug, and to the extender

(1) In low-range operation, the G1 circuit is

valve.

operative (para 2-14c (1)).

(2) Pressure is prevented from bleeding off

(2) At the low-intermediate and intermediate.

high shift valves, TV pressure exerts a downward

past the ball check valve at the right of the manual

force which retards upshifting. Thus, the more the

selector valve. When governor pressure is sufficient

to overcome spring pressure (plus throttle (T)

vehicle engine throttle is opened, the later up-

shifting occurs. When the valves have upshifted,

pressure) above the lockup valve, it will force the

lockup valve plug and valve upward. This will

TV pressure is blocked.

charge the lockup feed line.

(3) At the main regulator modulating plug,

(3) At the main pressure regulator plug,

downward pressure increases main pressure by

pressure is exerted against the lower surface area of

moving the main regulator valve downward. Thus,

the plug. This tends to raise the plug. But, when the

as throttle opening progresses, main pressure is

lockup valve is upward, main pressure above the

boosted.

plug keeps it from moving. When the lockup valve

(4) At the extender valve, TV pressure tends to

is downward (converter operation), the regulator

push the extender valve downward. In figure 2-4,

plug moves upward to reduce main pressure as

the valve is upward because both spring pressure

governor pressure rises. The orifice in the governor

and main pressure oppose downward movement.

pressure line restricts flow to prevent movement of

The effect of downward movement is an increase in

the plug being too rapid when it does move.

pressure required beneath the extender valve ball to

d. Rear Governor (G2) Circuit (green, black-

unseat it. This action influences trimmer operation

fig. 2-4).

(para 2-16i).

(1) Rear governor (G2) pressure is produced

(5) TV pressure actually connects into the

by the rear fluid velocity-type governor (para 2-2).

throttle (T) pressure circuit while either the low-

intermediate shift valve or the intermediate-high

This pressure is directed to four points and is the

primary control force for all automatic upshifts and

shift valve is downward. This connection occurs in

downshifts between ranges.

the valve bore areas near the upper ends of the

valves. Thus, there is pressure in the T pressure

(2) G2 pressure is directed to the lower surface

circuit prior to upward movement of the throttle

areas of the low-intermediate blocker plug and the

low-intermediate shift plug. This produces an

valve to a point which connects the TV and T

circuits. T h i s pressure retards the upward

upward force at each plug. The low-intermediate

movement of the lockup valve and delays lockup.

blocker plug is shown in its downward position,

However, when the low-intermediate and in-

being unable to move against its spring and

inhibitor pressure. The shift plug (and shift valve)

termediate-high shift valves are both upward,

there can be no connection of the two circuits

are shown in their downward positions. They have

except at the throttle valve.

not moved upward, in this instance, because

g. Throttle (T) Pressure Circuit (green, yellow--

throttle (T) pressure, spring pressure, and inhibitor

fig. 2-4).

pressure is sufficient to prevent upshift.

(1) At approximately 5/8 inch of throttle

(3) G2 pressure is directed also to the lower

opening (upward movement of throttle valve),

surface areas of the intermediate-high blocker plug

2-13