PUMP & MOTOR GP 2884955 - Caterpillar

Illustration 1 g00563134
Return Valve
(1) Thermal Bypass Valve. (2) Return Manifold.
Thermal bypass valve (1) is integral to return manifold (2). The return valve directs the case drain oil and the return oil to either the tank or the hydraulic oil cooler. Return Manifold
Returning oil from the following systems flows to the return manifold (2):
Propel system
Vibratory system
Steering systemThermal Bypass Valve
Illustration 2 g00563202
Thermal Bypass Valve
(3) Cap. (4) Piston. (5) Actuator spring. (6) Pressure relief spring. (7) Valve.
Thermal bypass valve (1) is a cartridge type valve. The thermal bypass valve controls the amount of return oil through the oil cooler. Oil flow through the oil cooler is dependent on oil temperature.
Illustration 3 g00732777
Oil Flow To Cooler Graph
When the hydraulic oil temperature is below 65°C (149°F) the thermal bypass valve directs flow to the tank.When the hydraulic oil temperature reaches 65°C (149°F), additional oil is directed through the oil cooler. As the temperature of the oil rises, the bypass valve closes farther. Total oil flow to the cooler is 54 L/min (14.2 US gpm) when the temperature of the oil reaches 71°C (160°F).