Replaced HYD. filter??? Weak backhoe

[Marchetti]

Hey Guys,
After searching and reading the manual, I'm still not 100% sure I know what to do
I bought a 79 580C. Engine Runs strong.
But I'm not really sure what the thing is capable of. never owned anything like this.
The loader can lift the front end off easy.But, it does come back down over night. I can see I have a leaky cyl. That can be fixed.
I'm not sure if The backhoe is working correctly. I know there is a trick to locking it. I can't do that unless I have gravity on my side. (facing downhill)
The Boom tends to drift away from the backhoe when it is hot after a hr of use. Not sure what that is. I have read about putting a gauge on it to see what it says but honestly that's beyond me I think. maybe not.
Also In reverse it makes kind of a whining sound similar to a loose belt. I checked that . not that.
All the filters have been changed Hyd., fuel, oil, air. are there screen that I do not know about. Fluid seems clear.
Yesterday I used it extensively. I was pulling creeping juniper bushes out. runners everywhere. I thought is would tear thru those, but it seemed to struggle. got worse as time passed.
What else
OH , there are 5 levers for the backhoe
2 stabs
one for the bucket
one for the dipper? and one for the boom
Should I be able to operate this simultaneously? Because I cannot. I have to position And kinda stop and start to lets say scrap the ground. I don't think that's right..
Sorry it long but nowhere else to turn.
thanks

 

[bigdeano]

It's probably operating normally for a backhoe of that age. The spool valves will have some wear which will let the cylinders drift slowly even if the cylinder seals are good. Can you raise the rear tires off the ground with the stabilizers, and will it stay up for a while? If so then you're probably doing fine.

With a backhoe that runs off only one pump you can't operate more than one function at a time unless you feather the valves. The whole flow will go to the easiest to move cylinder unless you close that valve part way. You will learn how with practice. I could sometimes move three things at a time on my Case 420.

If it gets weak when it heats up, the pump is probably worn. You should measure the pressure cold and hot at idle and at a higher rpm.

 

[LarJea]

On my Case 580B I had I could operate the boom, dipper, bucket and swing at the same time. As far as locking the boom back, when the boom is almost all the way back, quickly push the lever the other way forward then back to neutral and the boom will travel back the extra distance needed. I know it doesn't make any sense that it would work that way but that's how it's done.

 

[Marchetti]

Thanks. Altgough I now have two different answers to simultaneous function. Where di I put a pressure gauge?

 

[Marchetti]

So guys where can I test the pressue from? Anyone know?

 

[bigdeano]

You can disconnect a hose that goes to a cylinder at the valve and screw the gauge in instead. Actuate the valve and read the pressure.

 

[Marchetti]

All the gauges I saw were 1/4 npt. Its gonna be a weird adapter. I thought there was a specific place? Wrong?
Thx

 

[jenkinsph]

All the gauges I saw were 1/4 npt. Its gonna be a weird adapter. I thought there was a specific place? Wrong?
Thx

You need a hydraulic gauge (about 5000 psi rating) and a short hydraulic hose for this. One end of the hose should be adapted to connect the gauge, the other end should match the fitting on the hose you remove. DO NOT USE LOW PRESSURE GAUGE, HOSE OR FITTINGS FOR THIS.



Understand before you proceed that used backhoes will require maintenance. Some of these repairs can be rather involved but can be done if you take the time to learn about it..

 

[Marchetti]

Thx. I might let a pro do it
Ine other question I can't seem to find the lift capacity in lbs for the loader. 3000, 4000?? less more?
Thanks again for your help

 

[CJONE]

If it gets worse as the oil heats up it is almost always a pump. These units usually have 2 circuit pumps on them. I would get a hydraulic flow tester or pay somebody to test it for you. It will save you a lot of headaches. CJ