wrote in message
...
I have a mid 70s Case CK780 backhoe. The thing had seen lots of abuse
before I bought it and I have used it pretty hard since. The power
of
the hydraulics has gotten weaker over the years. I used to be able
to
kill the engine by trying to push or pull too hard. Now this doesn't
happen. So I'm thinking that the pump has a lot of wear. Over 30
years
ago I used to repair gear pumps in a lumbermill I worked in by
grinding the end plates of the pumps to remove scoring. But I don't
know how much more pressure the pumps put out after this repair, it
was just what I was told to do and I did it a lot. Considering the
age
of the tractor I'm wondering if I might just be better off buying a
new pump and also if there is somwhere else I should look for the
lowered power of the hydraulics. The power loss has been gradual
over
the years so I'm thinking it's probably the pump.
Thanks,
Eric

I bought a new pump from Bailey after fussing too long with the wrong
size of old Danfoss pump, which I had to regrind like you.
http://www.baileynet.com/#prodcat/Hy...type/Gear-Pump
Second on the pressure gauge, glycerin filled to damp the needle and
located where you can see but not break it. 4000 PSI should cover the
possibilities but not be too hard to read at half scale. I think
common pressures run around 2500 - 3000 or you could check the hose
rating.