The 8931-230 uses 6-2/3 gal. (25.3 liters) Silicone Oil, part number 5-1070-x.
Depending on availability, you can order the silicone oil coolant in a variety of sizes:
|Part Number of Silicone Oil||Container Size|
For convenience, Bird offers various maintenance kits for the 8930 series that includes the silicone oil here: 8930 Series Repair & Maintenance Kits.
Please see the Material Safety Data Sheet (SDS) for further information: Silicone Oil SDS