Oil cooler bypass valve actuating means

In an oil cooler bypass valve including a valve housing having an elongated valve chamber communicating with oil supply, oil return, cooler supply and cooler return lines;

• and a valve member having a cooling position for directing oil from the oil supply line to the cooler supply line for circulation through a cooler and from the cooler return line to the oil return line, and further having a warm-up position for directing oil from the oil supply line back to the oil return line, an improved valve actuating means for moving the valve member between the warm-up and cooling positions, said valve actuating means comprising:
• a main spring engaged between said valve housing and said valve member and operative to urge said valve member toward said warm-up position;
• a thermostat having a main portion and a pin extensible from said main portion in response to an increase in the temperature of oil in said valve chamber, said pin being engaged upon said valve housing;
• a relief spring engaged between said valve member and said main portion for moving said valve member toward said cooling position upon extension of said pin relative to said main portion, said main spring being compressible to enable movement of said valve member in one direction under the influence of relatively high pressure acting on one side of said valve member, said relief spring being compressible to enable movement of said valve member in the opposite direction under the influence of relatively high pressures acting on the other side of said valve member.