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| Illustration 1 | g01031728 |
Torque converter hydraulic controls (1) Oil filter (2) Torque converter (3) Transmission hydraulic controls (4) Torque converter screen (5) Body of torque converter outlet relief valve (6) Transmission charging pump (7) Torque converter outlet relief valve (8) Magnetic screen (9) Hydraulic oil reservoir (10) Transmission oil cooler (11) Torque converter scavenge pump (A) Pressure tap for oil pressure (on filter) (B) Pressure tap for torque converter inlet [P3] (C) Pressure tap for relief valve (D) Pressure tap for torque converter outlet relief valve (E) Pressure tap for lubrication | |
The hydraulic system consists of two control valves for the torque converter. These valves are the torque converter ratio valve for torque converter inlet pressure and the torque converter outlet relief valve for torque converter outlet pressure.
Torque Converter Ratio Valve
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| Illustration 2 | g01031470 |
(1) Transmission selector and pressure control valve (2) Torque converter ratio valve (3) Slug (4) Spring | |
The torque converter ratio valve is part of transmission selector and pressure control valve (1) .
Torque converter ratio valve (2) controls the maximum oil pressure to the torque converter. Torque converter ratio valve (2) prevents damage to the torque converter components when the engine is started and the oil is cold. Torque converter ratio valve (2) limits the maximum pressure to the torque converter to approximately 980 kPa (142 psi). This pressure is not adjustable. When the oil pressure exceeds 980 kPa (142 psi), the oil is directed into the transmission case.
Relief Valve (Torque Converter Outlet)
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| Illustration 3 | g01244517 |
Top view of torque converter housing | |
The torque converter outlet relief valve is mounted on the torque converter housing.
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| Illustration 4 | g01031473 |
The outlet relief valve maintains the pressure in the torque converter. The setting of the torque converter outlet relief valve is approximately 415 kPa (60 psi).
Shims (7) are used to make adjustments to the opening pressure of the torque converter outlet relief valve.
Oil flows into valve body (1) through inlet passage (4) . When the pressure in the torque converter is approximately 415 kPa (60 psi) poppet (3) is moved off its seat. Oil pressure now moves valve spool (5) down against the force of spring (8) . When the pressure of the oil becomes greater than the force of spring (8) , the movement of spool (5) allows the oil to flow through outlet passage (6) . From outlet passage (6) , the oil flows to the transmission oil cooler.
When the pressure in the torque converter falls below 415 kPa (60 psi) spring (8) pushes spool (5) up to limit the flow of oil to the transmission oil cooler.