I was doing a machine inspection on this excavator on Friday and noticed that its low on hydraulic oil. It had all fluids changed before I purchased it and then it was vandalized heavily before I needed to do again. When it was repaired they did a complete fluid change on it. I have the high dollar CAT oil and need to add some obviously. I've not ever added hydraulic oil to a machine of this size and don't have a manual yet. Will the hydraulic tank be pressurized? I would assume that since I am adding fluid and not draining that an air bleed won't be an issue? All help is appreciated.
Before going anywhere, did you have the front-end equipment in the correct position to check the hydraulic oil level..? As you don't have a manual I'm not sure if you are aware there is a "correct position" for the implements before checking the oil level. See below. Also make sure the machine is on level ground, that can also make a lot of difference to what you see in the sight glass. The hydraulic tank will not be pressurized when the oil is cold, only when warm. Obviously with any tank like that that builds pressure during operation be careful when you first crack the cap even with cold oil.
Nige, thanks for your response and concern. I had the machine in that configuration roughly but it was not completely level. The boom/stick and bucket were set like the diagram. The off camber setting could have contributed to the hydraulic sight glass being low but I saw none in it. I would say it was not level but not a significant slope either. Front to back on the tracks deviation might have been 6-8". I would say it was 3/4 of a bubble out of level from memory. I'm used to walking by and seeing it in the sight glass pretty much always.
Also....the 315 next to it, sitting similar, on same slope had oil in its glass. I used it as my reference point. Not exact but pretty close to the same setting.