Hello All, I had a loader pivot pin that would not take grease. It was the right side pin located at the lower end of the vertical link that connects the loader arm to the bucket curl cylinder rod pivot. I removed the pin in order to clear the obstruction in the grease pathway, and when I did the assembly shifted very slightly upward. It was so slight I figured I could just align with a come along when ready. However, I let the machine sit overnight while I cleaned the pin and now the unconstrained right side curl cylinder has extended about 5 inches further than the left (still constrained) curl cylinder. In order to reassemble the pin and link I need to close the only the right side cylinder. Does anyone know how I go about this now that its travel is out of synch with the left. Any help will be appreciated. Thanks.
pull the pin on that cylinder so you can line the hole up for the pin then use the hydraulics to line the cylinder pin back up.
Hi Billrog. Thanks for the reply. I appreciate your suggestion, but am not sure how pulling that pin will be any different from the situation I'm in right now. Assuming any movement in the bucket curl lever will move both cylinders equally, I don't see how that will get them back in synch from the 5 inch difference I see now. If I were to disconnect the hydraulic lines to the unconstrained cylinder on the right side, would I then be able to slide the piston in and out manually? Thanks again.
The cylinders aren't "in sync" as such, they both see the same oil pressure and move together because they are both connected to the bucket. If you work the hydraulics, you will find that the disconnected cylinder moves on its own as it has less resistance to movement because it isn't connected to the bucket. Or alternatively as you suggest, you could disconnect the hydraulic lines and move the rod manually, but you will lose some oil.
Hi Cmark. Thanks. I had assumed that the oil drive pressure is so great (and uniform between the two cylinders) that since they are not "in synch", they couldn't be put right again using only the control that drives them both. I'll give it a try.
Pressure and flow are tricky things to conceptualise. Consider the analogy of a dam wall with two identical floodgates. The first floodgate has a hundred people holding it shut, the second floodgate has one person.
Use a jack to move the bucket to line up the holes. Or a ratchet strap with a bungee strap around the control handle. It's sometimes easier for a novice to line up this way than with the hydraulics.
Thanks to those who have responded to my post. I figured a photo might better explain the issue. Based on cmark's reply I should be able to raise the bucket off the ground, and once the weight of the bucket is being supported by the left cylinder, curling back on the tilt lever should pull the right cylinder (with no load) further than the left, allowing me to line up the pin. Does that sound right?
Crack the lines and push the rod in by hand
Hi Dieselmonkey thanks for the reply. Is there anything I'd have to do to bleed the air out of the system after cracking the lines and losing oil? Does the hydraulic system handle that OK?
The two cylinders are joined together hydraulically. If you lift the loader arms, the weight of the bucket will extend the LH cylinder and the displaced oil will enter the RH cylinder making it retract, with the effect of moving things the way you want to go. But that's too hard. Just leave it as it is, curl the bucket and the LH cylinder will move on its own. Edit. Should have said RH cylinder will move on its owm.
I wouldn't worry about bleeding air. After you get it together it you can fully cycle the cylinders and that will bleed the air sufficiently. However keep in mind that some some of JCB British Standard Parallel Pipe fittings use o rings and you may have to change them after cracking the lines (usually they are ok as long as it's not a very old unit). Hopefully all goes well.
I've had this a few times on JAN 3cx and 212 backhoe.
That will all work, but I'd put a block of wood and a bottle jack under that loader crossmember and jack it up by hand. Sure it will take longer to set up, but you want to guess how many times you're going to climb up and back down trying to get the pin to go through before you give up and use a jack?
Thanks to all who posted on this issue. Cmark nailed it. Once the machine was running I just touched the curl lever inward a few times and walked it right into alignment. The greased up pin in slid right in. Not what I expected, but exactly what you said. Thanks again!
and the advise was FREE! Time for a beer.