Excavator bucket curl

[RKC]

Excavator bucket on my Volvo EC240 has stopped curling and now seems to be only working in one direction. Any suggestions as to what the problem here maybe?

 

[funwithfuel]

If its only bucket, I'd say you have a bypass issue in the cylinder. If you hold bucket curl over relief, does the engine load up?

 

[RKC]

If its only bucket, I'd say you have a bypass issue in the cylinder. If you hold bucket curl over relief, does the engine load up?

The engine does not load up when holding bucket curl over relief. Once it moves to dump direction it stays stuck and doesn't curl

 

[funwithfuel]

Does the cylinder get warm, or can you hear/feel oil rushing through it? If so, it's time to rebuild the cylinder

 

[Delmer]

If it dumps but won't curl, that's odd. If it was the other way around, it curled but wouldn't dump, then the hydraulic cylinder could be leaking enough internally that it's operating as a one way cylinder, the rod becomes the piston if the piston is loose from the rod. But it won't retract the cylinder that way.

I'd check some pressures, and flow at that cylinder. That can be as easy as seeing if the hoses flex when you try to curl, and seeing if anything gets warm like funwithfuel said. Then use an actual pressure gauge, OR look into the control valve based on what you find.

 

[RKC]

Tried swapping ar2 pressure with br2 pressure and now bucket curl function is working but dump function won't work.

 

[funwithfuel]

Then it sounds like the RCV (joystick) is not sending oil to the bucket dump circuit. What series 240 do you have?

 

[RKC]

VOLVO EC240LC C03966

 

[funwithfuel]

Ok. That's more Samsung than Volvo. Negative control. Have you any way of gauging the signals to the spool caps of your bucket circuit? Preferably at the same time.

 

[RKC]

Ok. That's more Samsung than Volvo. Negative control. Have you any way of gauging the signals to the spool caps of your bucket circuit? Preferably at the same time.

At the moment don't think i have anything to gauge the signals to the spool caps of the bucket cylinder.

 

[Kobelco ireland]

If the problem changed when you swapped port relief valves ar1 and br1 then you have a faulty port relief valve.

 

[Kobelco ireland]

I only half read your post did you swap the pilot hoses or the relief valves

 

[funwithfuel]

Good catch, i took his statement to mean he swapped hoses, not port reliefs. We'll have to wait for a reply to see what was actually done.

 

[RKC]

I only half read your post did you swap the pilot hoses or the relief valves

My bad. The pilot hoses behind the cap were swapped not the relief valves. Replacing the right side remote control valve now to see if it is rectified.

 

[funwithfuel]

I would blow the hoses out first, make sure there's no debris blocking the fittings on either end. Make sure you can blow through from either end. If the hoses check out ok, then i would replace or rebuild the RCV.