A hydraulic pump problem

I finally have time to troubleshoot a Stanko SMO 32 CNC machine that I bought a while back and the first and probably biggest problem is the hydraulic pump. First and obvious problem is that the interference suppressor (I think?) is broken off. I already ordered a replacement, but I'm not sure if the pump is functioning correctly. When I press the button to force the pump to turn on it starts making a noise like a compressor, so I guess it's trying to do something, but it doesn't seem like it's creating any kind of pressure. I think that maybe some kind of valve or a gasket is leaking or sth? Here is a video of how it looks like: 

Any ideas? Should I just wait for the replacement suppressor and it might fix it? Or is it sth with the pump itself?

I'm pretty sure this is a pump for the tool holder, ie. hydraulic grip for ISO40 tooling. This machine is very similar in all of the equipment to old Maho machines and it has a second pump for lubrication from Vogel - which I'm 100% sure is for lubrication, cause the label says so.

Btw, if someone knows this stuff better than I do, here is the manual: www.dropbox.com/sh/wlih7qlsraslpe1/AACT8...AKUHPnHZ8glHlTa?dl=0 (it's in German, though)

I think that the Vogel lubrication pump is also not functioning properly for some reason. The error number shown on the machine is 47, which is "hydraulic device not turned on", which I guess may mean both the hydraulic pump for the tool changer or the lubrication system. In any case Vogel doesn't seem to work and pressing the buttton ton the enclosure doesn't turn it on either

Thanks @andypugh and @aciera! I'll take a look into it, but now that I think about it there is one more piece of information that makes this a bit curious.

When I bought the machine I was able to get it to turn on and get to the phase where I could move all of the axis. Of course the tool holder didn't work, but the error didn't show up either. I also remember that when I pressed a button on a Vogel lubrication pump it tried to pump for a short time. Now when I press the button nothing happens. Not sure if it means anything, maybe there is another reason on why the pump didn't turn on.

Anyways I'll try to go through the documentation once again with the insight from Aciera and then I'll see about the pump. But then I'll also see how it looks like when a broken electronics part arrives.

The bubbles in the center chamber look wrong. Is it 3 phase and possibly rotating the wrong way?