Case 310B, new to me general questions

I recent bought what I thought was a 530 CK
until I went to get it and it is a 310B.
Nonetheless, it runs great and is like new,
wear wise, very little slop. I do have a
few questions on jt:

1. After finding the hydraulic reservoir,
the one built into the loader frame for
running the loader and backhoe, I know it
is low. The problem is, it has something
clear in it. Its not water, and we don't
think it is mineral oil. It doesn't really
have any distinctive smell either, just
like a general oil smell. Is it possible
someone put mineral oil in it? If it is
mineral oil, should it be changed to hytran
or something else?

2. Parts: is it possible to look up parts
diagrams for the entire machine online? All
I am finding is the backhoe and loader on
Case's site. I am looking for a paper set
now, but for #3, I'd like to find a
drawing.

3.On the throttle, how is it supposed to
work? It appears that possibly the foot
throttle part of the rod(?) Is stuck in a
position so it only runs about wide open.
There is a spring hanging down on the left
side that I don't know where it goes. The
foot throttle itself and the rod moves
freely.

Any other advice you can give me on it?

It will be a limited use farm machine.

Thank you.

I do have manuals for the 310 B loader backhoe if interested . my e mail is [email protected]

If the oil is not whitish it could be hydraulic oil since most of hydraulic oil is thin.