Hydaulic Problem??

[Richard Segal]

Greetings,

I have a 90 9020V that is having a steering related problem.  When
I move the steering wheel, I hear a groan everytime I move it.  I
noticed that the hydraulic fluid (Pentosin) was a little low and
brought the car to the mechanic.  He diagnosed the problem as a
slight leak from a cracked hose and cut the bad spot from the end
of the hose, reattached it, and added some fluid.  Sound
disappeared but one week later, the same problem again.   Could
this be a bad bomb (hydraulic accumulator) or a bad hydraulic
pump?  If the latter, I would think that the sound would not have
disappeared when fluid was added.  Your assistance is appreciated.

Rich