UA544142 -1 (Goodrich Airframe Mount)
UA544494 -1 (GE Airframe Mount)

The oil cooler assembly has a finned core and collector housing. The oil cooler assembly contains passages that direct the flow of oil to be cooled. The housing is a casting that is brazed to the core. The IN and OUT oil ports are found on the top of the oil cooler. A tube fitting is given in each port to connect the oil cooler to the Integrated Drive Generator (IDG). A bypass relief valve assembly is installed on the housing between the IN and OUT ports.

The hot oil goes into the oil IN port and flows through the passages in the core. The hot oil will cool by the air flow around the passages, and exits through the oil OUT port. If the oil passages become clogged, or if oil viscosity is high because of low temperatures, the relief valve will open. When the valve opens it directs oil flow from the IN port, through the relief valve to the OUT port. This will cause most of the oil to bypass the cooler core.