Seems like one problem after another. About to load machine up and the bucket cylinder went from a minor seep to an active flowing leak. I installed blocking between the barrel and stick, and supported the rod and used the machine hydraulics to push the rod out. We did this without machinery lifting assistance and pretty obvious This will be a serious PITA to assemble being at an odd downward angle and the rod probably weighs 200+lbs with the cap and everything on it. My plan was to reinstall the rod on the linkage to hold it so I can get the nuts off. The main piston nut is at 2600ft/lbs and not sure what wrench we might use to handle that. I know many people use a pipe wrench and we have a few 36"ers but that might be too much for even that wrench, plus I am not sure we really want to damage the nut with a pipe wrench. I am curious how nice these would go back together? The books insists on a ring compressor tool to compress the piston guts for install. Not sure if that is really needed? All in all, I am trying to size up this job as one we should even attempt in the field?
My 2c would be get the cylinder off the machine. It will make the job much easier.
The main issue is how much force might be required to assemble things? Seems many make light of it but my only experience was with the boom cylinders and we literally had a track skid steer at full tilt and could not even get the rods to MOVE in the cylinders with all lines disconnected. We ended up pulling them and the local shop used hydro power to get them apart. However, the bucket cylinder head came off pretty easy and broke loose just taking the bolts off. That was promising. No clue how easy the rod might have moved because we just hydraulicly pushed it out. My only thought on keeping the cylinder in place is support but now that I am thinking more, I guess it is possible to remove the cylinder and move it down to the bucket mount which is about 5ft high, and we could set it up horizontal. Almost seems like a careful vertical approach could work well if supported right to use the component's own weight to assemble things. I see horizontal as being really tricky to center up just perfect.
We have done bucket cylinder in the field by taking off and making wooden supports and using straps then fixed it upright to the dipper which we've positioned at an angle to allow this, then used block and tackle ( chain hoist) dangled off a 2nd machine to give us true vertical fine control. Getting seals back in is a patience job, but gravity has worked as far as getting rod back in, unless my memory is clouded. All the best.
If you're planning to fix the cylinder yourself, then leave it in place. If you had the equipment to take the cylinder apart, then you wouldn't be asking. The other option is to take it off and pin it to a suitably sized drawbar to break the nut loose at an easier height. A pipe wrench is not going to be enough to get that loose. Cutting a wrench out of steel plate might work.
I still can't decide if it's worth it to do in house by the time I screw around building a wrench and a fixture I think it's easer to just give to hydraulic shop the has all the right equipment. It pains me to say as I like to do everything in house.
I'm just Joe Farmer, but last year I hyperextended my thumb cylinder on my JD200lc trying to roll over a stump. I just watched a few youtube videos after getting quotes of $800-1200 to rebuild it. I spent $70 on a rebuild kit and tore into it. A 3ft pipe wrench with a cheater bar worked just fine to pop the end nut loose. I figured the nut didn't have to look pretty, just hold the piston on. The thread locker for that big of a fastener was the tough part to stomach. $30 for a big bottle when all I needed was a few drops. I had to take out the pin to get the rod out, then put the rod back in the boom with the pin to hold the force of the pipe wrench. All the while supported by rag covered wood cribbing. I suspect if you have a strong helper you may be able to take the bucket off and extend the boom all the way out to get it low enough to work on. Only 'tricks' I can suggest is to let the main gland ring soak in almost boiling water for 5 minutes before trying to fit it over the piston, and crack the fitting at the top of the cylinder so air can bleed out when reinstalling the rod. I found some rag covered 2x4s to be adequate protection when reinstalling the rod.......and a STRONG set of helping hands. Good luck my friend. It was sure easier than I thought it would be. Just a few cents from my own experience (VERY limited at that). Your mileage may vary.
Well, we have success! Machined a custom wrench from 1 plate, built to handle 15,000ft/lb of torque and used the right cheater system and could not get much easier. Was calculated to need just a bit more than my weight to break loose and I bounced on it once just a bit and came right off. No biggy. Wrench took some time but we will have it around for many things to come. Now on to the reseal and reassembly.
Wrench sounds the nuts! Love it when plan comes together.
Something like this you mean...?
YUP! Someday when we have more time I might like to make an interchangable hex core on the waterjet amd splines so we can adjust the angle better but for now, this will do. No idea how common the 4" nut is but we got a tool for it now.... While waiting for the seal kit, I am still debating the required compression force to push the rod back in and if we will need a ring compressor for that. It looks like we will because those wear rings are pretty dainty. I am sure we can chew one up pretty easy.
Might be a little late for this comment but it may help someone. I helped a friend do a stick cylinder and before he started (with the cylinder leaking badly) he dug a hole , put the stick down in it till the cylinder was at a perfect working height. Sure made it easier.
Happy to report the cylinder in question is running and well. We probably got a little too wound up over it but I guess we were ill prepared on the last one. This one went perfect.
Great, did you have much difficultly feeding the seals and rod back in, or was it a bit of patience and a twist, and they were in?
Well, we removed the barrel and setup vertically as discussed, lowered the rod with another machine and once all its own weight was on the seal, I figured out that the head could be used as a nice symmetric hammer to knock the piston in. This only worked because of the nice tapered opening on the barrel bore and on the bucket and stick, they have hydraulic stoppers to handle being continually taken to max travel all the time. The seal walked in nice and smooth but there was certainly a point that I doubted our progress but I persisted. Actually the smarter and better was would have been to use stubs of all thread screwed into the barrel flange and just let the head pull everything together. Either way, it was easier than I expected.
With the amount of weight in the head, rod, & piston of a cylinder like that, generally if you have it vertical it all goes together pretty easy. It's one of those jobs that you can't rush.