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JCB 3CX 1999 – Extenda Hoe Problem – Wont move

rob500 ยท 2011-04-27 05:53

Hi fella's, I would be greatful if you could help me out with a problem with my new to me machine. I call it Extenda Hoe Woe Chasing any advice & help I can get at the moment. I'll try to throw up as much info as I can with pictures. The fella I bought the machine off, when he was showing me how everything worked, said he hadn't used the extenda dipper feature and he had had the machine for a few years. When I got the machine home and tried to get the hang of operating it, I couldnt get the pin out of the extend hoe. I think what had happened was the extender part had lowered about an inch and was pushing on the pin. I stood on the hoe backwards foot pedal, and the hoe came back that inch and i was able to get the pin out and locate it in the extenda hoe operating position. I jumped back in the cab and pressed the hoe out pedal and nothing happened. I kept on working on what I was working on, then tried the hoe out pedal again. This time it moved out about 14 inches. When I tried to bring it back, it stuck in the position it is in now. I tried pushing the return pedal while leaning on a tree, and also while pushing into the ground. The thing is locked solid. So thats where I am at??? The machine is a 1999 grey cab model. Everything else appears to work pretty good. 8000 hours, and no oil leaks etc. Am very happy witht he machine so far except for this feature which I woul dhave used a few times now if it were available. It is piped for hammer, but I dont have the hammer. I took some photos of the hydraulic lines and their position in case the extenda hoe has been hydraulically disabled as the hammer was used? The joystick controls on the hoe are 'excavator' layout as well - not sure if thats obvious looking at the lines? They dont match the sticker/labels in the cab anyhow. Im not sure if its something as simple as a isolation valve turned off, or have a buggered cylinder, or if its in the valves - not sure where to start, or where to fault find. When the machine is running and I press the hoe out and back pedals, the hydraulics sound like they are trying to do something, but nothing moves.

Replies9
  1. #1rob5002011-04-27 05:55

    more pics - not in order tho??

  2. #2rob5002011-04-27 05:58

    last pic

  3. #3alrman2011-04-27 07:56

    rob500, It's a bit hard to work out what is going on by those pictures. When you are attempting to move the extendahoe, & the engine loading up the hydraulics, do the aux hoses flex under pressure? Is that pedal for hammer same pedal for extendahoe? (pedal still has paint - doesn't look to have had much work) As it is loading the engine - then a diverter valve could very well be the cause - there should be a control switch somewhere to flick between hammer use & extendahoe use. Problem could be electrical or could be the spool sticking in the diverter valve. PS - looking at pics, I think aux hyd would more likely been used for an auger - the hoses are too small for a hammer.

  4. #4amyliveshere2011-04-27 11:47

    just a thought,are the adjusting screws too tight and stopping the dipper from moving.my mate who ran 3 x 3cx contractors had one serviced by a main dealer who tightened the screws too much and it stopped the dipper from moving.may be worth just slakening the bolts to see nick........

  5. #5rob5002011-04-28 05:54

    Cheers for the replies guys, I loosened off the 8 bolts a turn each and tried the extendahoe and its working now!! Awesome I think the plastic or nylon guides might have grown a bit?, or something to make them so tight. I'll have a look at resetting the gaps up when the sun is out tomorrow. I have to get hold of some of that Waxoyl, and give the system a good lube, then square it all up with the washer adjustments. I noticed with the guides all loosened, the extendahoe hoe is dropping when it should be holding. Might need a seal kit in that cylinder. That looks like a joy to get out!!! I also managed to contact the original owner / purchaser, so will ask about the pipework for the hammer. I dont want to fit a hammer. Im keen on a auger though. He did say something about not remembering if there was a secondary control valve for the electronic diverter. I cant find a switch in the cab? Thanks again!! Rob

  6. #6Deon2011-04-28 19:13

    Rust can also thicken the metal and make it very rough which can cause the slides to seize. Also if there is rust behind the pads, the swelling of the rust can forced the pads to bulge. Maybe just removing the rust with a grinder and reassembling will do the trick. I can't see much from here, I'm just giving you something else to look for because I think its more likely that the rust will swell than the nylon sliders.

  7. #7rob5002011-04-29 02:33

    Yea, I think you are right. The whole system was pretty rusty. Had a good bit of lube today, and a few hours use. So handy!!! Very happy

  8. #8Deere John2011-04-29 05:58

    So, looking at the bright side, you've got an 8,000 hour hoe with a nice, tight new extendable section. Gotta like that.

  9. #9rob5002011-04-29 16:36

    Yea I like the positivies in things - haha, you're right!!