poclain 75 ckb hyd fault

[david 68]

Hi,can someone help me.I have a Poclain 75 ckb 1983 tracked excavator,it has tilted onto the side & the hydraulics are not working.
I have filled the hyd tank with oil,still not working.
Been told there is a hydraulic electrically operated solenoid valve on the machine,which cuts the hydraulics out(safety reason)
Checked hydaulic diagram & shows solenoid valve.
Can someone tell me,where the valve is & how to reset.
thanks

[Muz]

Hi,can someone help me.I have a Poclain 75 ckb 1983 tracked excavator,it has tilted onto the side & the hydraulics are not working.
I have filled the hyd tank with oil,still not working.
Been told there is a hydraulic electrically operated solenoid valve on the machine,which cuts the hydraulics out(safety reason)
Checked hydaulic diagram & shows solenoid valve.
Can someone tell me,where the valve is & how to reset.
thanks

What do you mean tilted onto one side ? ... are you working on a slope ?

[david 68]

poclain 75 ckb

Hi,I meant that the tracks on one side have sunk into soft ground.
The digger is laying at a steep angle with the rear end(hyd pump end)sticking up high,arm end laying low.
Thanks

[Muz]

Ive no experience of that machine, but I assume the older hydraulics it uses, are fed by gravity, and your pump isnt getting any oil because of that, or it has air locked, (apart from any safety device stopping it) in which case they would have a bleed system, or some sort of priming set up to get around the problem .. I'd imagine electrics here would be primitive .. so you should be able to follow the lines for the pump inputs and outputs, and be able to see some electrical connectors onto a block of some kind, or where those flows enter the valve block. If your advice has been good, and you find a solenoid, put a meter across it and find out whats its doing ? try diconnecting etc etc

[david 68]

The latest,is?
Removed main hydraulic hose from tank to pump,a little dribble of oil coming out,not enough for the pump.
But the tank is full of oil.
There is a round disc which is spring loaded under the breather,in the tank.
What does this do?
Will this stop the oil flowing from the tank?

[Muz]

Maybe theres a filter in there thats blocked ?

[david 68]

Maybe theres a filter in there thats blocked ?

Hi,
Finally the hydraulics are working.
Problem was due to angle of digger,no oil was being fed to pump.
Filled tank to the rim,bled pump & then all okay.
But,when machine was slewed to opposite direction,there was to much oil in tank & was leaking from breather.
Drained excess oil from tank & now all okay.
Simple hydraulics systems are easier to work on,rather than the new complex systems.
The round disc in the hydraulic tank is a isolation valve to stop oil flow from tank,if changing pump,etc.
Thanks to everyone.

Also looking for a 3ft digging bucket for the Poclain 75 ckb Excavator 1983 model.