Issue in electric hydraulic pump system

[zmandell]

One hypothesis is that there is air in the line but there may be a larger story at play.

Please see the full length of this 60 second video.

A few details:

-the issue does not present when initially running the pump, but presents after making 10-15 presses
-I checked the hydraulic reservoir and it is full
-the noise seems to stem from a vibration at the outlet side of the system
-the noise is often followed by a more pungent hydraulic smell

 

[Delmer]

Knowing very little about enerpac pumps, I'll speculate in general about hydraulic pumps. Anything leaking or wrong with the pressure side would be obvious at 10,000 PSI. Unless it was the relief valve, but that's adjustable, easy to inspect, and would build heat if it was leaking, in addition to causing pressure loss.

Air in the system would by design be cleared after a couple of cycles with no load. The only way you could be getting air is a suction leak (don't know if that's possible of if the pump is submerged in oil), or the oil is foaming. Either one could make a wicked noise at that pressure, and explain the smell. Air in that system could diesel, making the smell even worse.

Of course there's always the possibility of mechanical problems like a coupling slipping or a bearing seizing up, I'd think those are less likely to make the smell, but if they did they'd be easier to find than the smell coming from the hydraulic reservoir.