jcb3c3

[crew_cab]

for the last few weeks my jcb 3c3 powertrain has had problems wil backhoe only works 1 leaver at a time then waite for few seconds before you can carry on this week end i had to use it on a foundation hole to get to the other side of the hole i had to reverse into the hole as i did this i lost all backhoe hydrolics with nose in air nothing as soon as it was leval agan they worked any ideas whats wrong is it pump ,fillter ,just dont know
anyone any idea's

[agrimax]

Sounds like the hydraulic oil is very low to me! With the pump at the front and the nose in the air,the pump will be starved of oil if it's low. Or it may (also) be drawing air through a porous hose on the suction side of the pump.

[crew_cab]

jcb 3c 3 powertrain have posted several times with problems mostly hydraulics the legs work ok and it will stand on legs with wheels of the ground just over a week. but will only work back leavers one at a time and wont stay up at all does anyone have idea is it the valve block or some thing else
if its the valve block can i change the seals in place or do i have to take it off thanks to all for replys

[agrimax]

You need to first of all verify there is plenty of hydraulic oil in it. As before,when the nose was in the air and everything stopped working,it suggests either very low oil level and/or air being sucked in,either through the suction side of the pump or elsewhere. Is the front loader working as it should? If it is,there may be an suction leak between the front loader control valve and the backhoe valve block.If not,then it's back to the previous answer and also the filter. Rams not holding up suggests air in the system,bad ram seals or worn control valve spools or an internal crack in the valve block.If the valve block is worn or cracked,it'll need replaced. The o ring seals in there are really only to stop oil leaking out and from dirt/moisture getting in.The spool rods are a made to be a perfect fit and if they become worn,the lot needs replacing......
Oh..and it's maybe possible that an arv valve is stuck in the rear block too..

[crew_cab]

oil level seems fine up to mark well just above have had the legs down and lifted rear of the ground for over a week and still has dropped about 4 inches but still off the ground tried the bucket and it drops as soon as you let go of the control levers
will try a few more times and if we carn't cure the problems will be sending it off to live in the sun in africa

[essexpete]

Is it just one service that is giving trouble?
The problem that arose backing into hole is more like pump cavitation dragging air in. Those problems always seem worse with dirty oil/filter and colder weather.
If just one service is really poor you might have piston seal leaking I side the ram.