TUBE AS 2609336 - Caterpillar

Never remove the fill/vent plug from the hydraulic tank if the oil is hot.Air can enter the system and cause pump damage.
Illustration 1 g00102817
The hydraulic oil tank is on the right side of the machine.
Park the machine on level ground. Lower the bucket to the ground with the stick in a vertical position, as shown.
Open the access door on the right side of the machine.
Illustration 2 g00687286
For a cold machine, maintain the hydraulic oil level in the low temperature range. For a machine that is at normal operating temperature, maintain the hydraulic oil level in the high temperature range.
Close the access door.
Illustration 3 g00833952Note: Refer to Operation and Maintenance Manual, "General Hazard Information" for information that pertains to Containing Fluid Spillage.Note: Perform Step 5 through Step 7 if the oil level is low.
Slowly loosen the fill/vent plug in order to relieve any pressure. Add oil, if necessary.
Check the O-ring seal of the fill/vent plug. Replace the O-ring seal if the O-ring seal is damaged.
Clean the fill/vent plug and install the fill/vent plug.