LEVER-GEARSHIFT 7M0847 - Caterpillar

Illustration 1 g01328889
(1) Transmission lubrication relief valve
Illustration 2 g00646729
(1) Transmission lubrication relief valve
(2) Spool
(3) Spring
(4) Ports to the transmission case
(5) Passage from the transmission hydraulic control The transmission lubrication relief valve (1) is located after the relief valve for the transmission hydraulic control. Transmission lubrication relief valve (1) controls the maximum pressure of the lubrication oil that is flowing to the transmission. Lubrication oil for the transmission comes from oil that is flowing through the pressure relief valve for the transmission charging system. When the oil from the transmission charging section of the transmission gear pump reaches the relief setting, oil will pass through the pressure relief valve for the transmission charging system. This oil is then supplied to the transmission as lubricating oil. If the pressure of the lubrication oil in the transmission lubrication relief valve (1) overcomes the force of spring (3), spool (2) will shift. This will allow passage (5) to drain lubrication oil through ports (4) into the transmission case.