JLG boomlift took to leaking quite profusely from the main lift cylinder so decided it was time to do something about it. Scanning through the electrical print it looks as if there are 56 wires to unland/disconnect in the lower main distribution enclosure running up the boom, eight hydraulic hose ends to plug and cap, then of course extract the pins the boom both pivots on, and pushes up with. I've been told these pins can be an SOB to get out. After conversing with "OFF" with the matter, we came to the conclusion I could use my shop gantry to hold the back of the boom elevated after lifting it clear of it's mounting(s) with the basket on the shop floor. I could then manually drive the chassis from underneath the hanging base boom to still have use of the shop. Given this is a life/safety type thing, I'm going to send the cylinder into the rebuild shop so everything can be addressed properly including counterbalance valve calibration. I have everything working as it should on the lift now and it does work well, but leaks a lot of hydraulic oil. When the boom is powered down, this lift cylinder is spewing almost a pencil diameter stream from the top gland about four inches high. This is a great increase from the "seepage" that has been there for years. Both the master, and slave cylinders for the basket level circuit leak a bit so sending those in also. I would repack the cylinders myself if this were not a piece of equipment that could possibly have an expensive lawsuit attached from failure.
It doesn't look like the easiest machine to work on. Best to have it done properly so hopefully you'll never have to take ir apart again.
Shipped my main lift, and basket slave level cylinders into the hydraulic shop late this morning. Should have both back the first part of the week. Man were those fittings tight on the main boom cylinder. Will be nice to not have hydraulic leaks on these cylinders as they always puddle. Once these are back I'll get the lift operational and send in the axle(s) spreading cylinders for service as the drive axle cylinder leaks so the steer can't be too far behind. The master level cylinder for the basket leaks also so it will also be sent for repair. I kinda/sorta deviated from the original plan and just dragged out my old AC-225 Lincoln welder and a known good box of 6011 welding sticks because we all know that deep penetration and float off of offending crap precluding inclusions offered on not so clean base metal these sticks guarantee, (this one is loaded with smeared paint when you touch it with a grinder) so I can have complete confidence in my welds holding chain "grab hooks on shown here: Then use my old Mack winch truck to offer some support: Just so I could knock the pin out that the cylinder pushes against to elevate the boom: 1845C Case skid steer wasn't enough capacity to lift cylinder so planned on using old "Fred" to hoist the cylinder from the center section: Wife says I'm "nuts" but what does she know????
Glad it held but I would have ground to clean metal and used 7018. 7018 is the recommended electrode for cast and/or forged steel like the hooks are made of. The thought of the boom crashing down while being underneath it warrants making it extra strong. A strap around the boom would have been a good idea too. The way the chains are pulling on the hooks isn't the strongest. I have seen hooks break in the U from side pulling.
Uh oh, sounds as if I fucke* up, or could have at least done better? It's held through 62mph winds in one storm, and 47mph in another since we finally got some rain around here ending the drought that was burning up anything growing.
It held but it's one of those things where you really need to consider what would happen if it failed. 6011 can burn through some paint and dirt but it's not ideal. It's always better to clean the steel as much as possible regardless what rods you are using.
Ah you're all set you have an old timer.
I agree with Welder Dave it does look scary.
It's all a learning curve. Now you know in case you ever have to do something similar in the future.
Got any more pictures of Fred? I'm digging the hoist. Is it all hydraulic or just the swing?
As Toby Keith said put into song; "Well Dave, I ain't as good as I once was, but...." I like razzing on people that absolutely know better than what I type and attempt to teach their trade. Kind of a respect thing you could say. Now to come clean: The supporting chain seen is actually G100 link/lifting chain surplussed from my shop gantry when needing additional under hook height so raised the beam. I replaced the lifting chain so could "pick" from the floor. You don't add, or modify lifting chain at all in a crane. Welded grab hooks are Columbus-Mckinnon G80 grade sourced from Rockford Rigging inc. for the purpose, and the wire used to mount them is .045 Hobart Fabshield 21B. Welder used was/is a 1982 build MillerMatic CP-300, (white face) w/10E feeder having a 400A Bernard/Tregaskiss mig gun. I did not want to use any shielding gas as was in an open doorway of the shop. My painted pink Milwaukee angle grinder, (which I call "Rosie Palm") and one of the five 5" grinders, (which I call her "little sisters") were used to clean off the old paint to bright shiny steel underneath. First with 16grit on a 9" disc, followed by a new 24 grit type 29 flap wheel. The base was very clean and bright once finished. I welded the hooks after blasting them in the tumble blaster with the "heels" canted 25 degrees towards each other, and the tops canted inward 15 degrees from the vertical plane. This was to ease the angular stressors placed onto the hooks from side loading citing the angles of the supporting chain legs. First, or root pass was hot and above 175 amperes indicated on the dial around the complete perimeters of the hooks. Penetration would well qualify as "deep". Second pass was a bit cooler and probably around 150 amperes with the third cover pass being yet a little cooler at first and cranked back up with a "weave" for adequate fill. Though not measured, the "fillet" is about 1/2" in width total around the hook base(s). These hooks were pre-beveled so no prep grinding to them was needed. They were however covered in shipping oil so the solvent tank and blast cabinet made riddance of this. The truck, well that is a 100K line pull Tulsa winch with 7/8" IWRC cable supporting the tug. It is drawn up snug but not like a banjo string. It's not thought to be going anyplace soon..... As a final check for strength of the welds and prior to taking anything loose in the boom, I backed the truck into the lift counterweight as seen and with the boom elevated and chained as you see, applied pressure and tension via the winch. If I would have kept pulling the front wheels of the truck would come off the ground due to the angular pull of the cable. Basically with the rear impact guard of the truck butted against the lift counterweight, it was solid abutment. I then neutralized stresses on the lift cylinder and easily pushed the pin through it's bores to free the lift cylinder eye. Backed old "Fred" over to the lift and set up for the "pick". The cylinder is actually hanging from the hook shown here as the photo was snapped afterward: I elevated the boom about four additional feet from the photo shown here to allow for adequate clearance: Here is the cylinder cleanly lifted clear of the chassis and I can see why the skid steer would not lift it as it loses so much capacity with height: The boom swings 90 degrees each way hydraulically with "Fred" so I just set the cylinder into the bed of my pickup: I sent rebuild kits in with the cylinders so they should be done pretty quickly. I've known this lift over 30 years myself personally and it's had great care but it is DAMNED expensive to have this kind of work done. It was allowed to leak till it became a deluge affair each time the boom was driven down, so time to facilitate repairs. I do have an AC-225 Lincoln "buzz box" welder I purchased new in 1974 to teach myself to weld. Never have had any formal education in the field of welding as far too stupid to learn anything, (so I'm told). The 6011 electrodes mentioned are probably that old too or maybe 1976 at best when that machine was replaced with my first engine drive which was a Hobart Bros. G-213. With DC capability, never went back to AC stick welding. Now with a 500A Perkins diesel powered Hobart Bros. engine drive machine and suitcase feeder, I seldom use stick any longer. You guys think this looks sketchy or scary, you should see some of the crap repairs I clean up and repair proper in farm equipment sometimes..... Here is a cut sheet of the wire used and like very well. It fits a plethora of applications in reality and I always keep it in a plastic bag unless being used: https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/datasheets/Fabshield21B.pdf Well, it's after 5:30am and time to get busy so will close for now. Being retired and having this much fun leaves me not as much time to spoil the grand daughters, so need to get back onto that today. Hope you all enjoy the cheap entertainment provided. I know several can do better but this job is good enough for who it's for and hasn't cost much so far..... Thanks,
I've had Fred over 35 years now so can probably scrounge up a few photos. Crane body is a 1956 built Pitman Hydra-Lift. It is hydraulic and manual operation both. The main lifting apparatus is a Tulsa model 19R mechanical winch driven by a Chelsea transmission mounted PTO. Vertical positioning of the boom is both mechanical, and hydraulic, but side to side swing is hydraulic. Boom extension is purely mechanical and a pain int the backside. Here I am pulling the boom out longer for picking the cylinder:
You could have just skipped all that professional business and cleaning and prepping and just hit a couple of passes with 6013 . . .
I was attempting to help Welder Dave control his blood pressure.....
I was always under the impression you never welded heat-treated lifting chains or hooks, for fear of failure, as their strength is seriously affected by welding, without post-weld heat treatment again? But what would I know? I'm only an old Catskinner who's a bit of a sissy when it comes doing things that risk my neck. I'd at least have hooked the chains a lot further up the boom, to reduce the leverage on them. In fact, I'd have 'em attached to the top of the boom. Just my 0.02c worth, YMMM. Lifting & Rigging Equipment — FAQs | Ranger Our experts have compiled a comprehensive list of FAQs to provide you with all the information you need to know about lifting chain slings. Read more here! www.ranger.com.au
I have several of those weld on grab hooks in the shop. I have a friend at the heavy haul yard in Morton, IL and he calls me when one of the regular haulers has a new trailer and would like customized anchorage points welded to their trailer. I've used both these hooks, and D rings for many years without problem. All are G80 rated and it's usually Fabshield 21B wire used. I've not seen anything pulled loose, or off myself but I'm sure not everything gets back to me. This is all new Caterpillar equipment leaving the manufacturing plants in the area. You are very correct in lifting chains, or hooks. They bend, or stretch and they are scrap. I don't think these are the same as the only way to attach them is through arc welding. They are commonly used for the application of tie down securement. I thought about placing the hooks further up the boom toward the basket which would lessen the cantilever effect, but given the tensile strength rating of everything used, didn't see any problems. This of course was verified with my impromptu "testing". One of grandpa's favorite sayings to me was and I quote: "Boy if you had a brain, you'd be dangerous"..... Talked to hydraulic shop this morning and they are into the cylinders already. No foreseen problems except they want to install new counterbalance cartridges due to age which I agree with. As mentioned earlier they'll be right when they come back.
Why would you make up a bogus post about what you welded the hooks with? A whole lot of trying to sound like you had everything covered. First I doubt the hooks are G80 grade and if they are should have come with specific welding guidelines and what filler metal to use. G80 is high alloy material. (CM only has that style of hooks in grade 30 by the way) The most glaring error you made is using Fabshield 21B. It is kind of the 6013 of flux-core wire. It's a little better but still not designed for dynamic loads and certainly not designed for welding G80 hooks. Notice how it says charpy impact values NA. 7018 or equivelant isn't even the right filler metal and Cat or its dealers would never use 21B nor would any crane outfit for lifting purposes. I think you've lost all credibility by posting bogus information and I don't believe most of your updated story concerning the steps you used to weld the hooks on. I try to give sound welding advice and critique learned over decades of practical and instructional experience. Kind of the same way the experienced mechanics give their advice. I try not to call people out but offer better options to them. It's not to insult them but there are times when it needs to be strongly pointed out something is extremely dangerous and wrong, like welding steering components on a vehicle licensed for the highway. I also point things out so others won't copy bad practices. I don't want to see anyone get injured or worse killed because they took a short cut or did something dangerously. I'm not on the forum to play dumb games. I've got some great advice that has helped me immensely and try to return the favor.
Quite simply to get under your skin obviously. That boom has been hanging just like that about a month while I freed up the stuck engine in Fred the crane truck. If it were going to fail I'm reasonably confident it would have done so by now. My apologies this job is not up to your standards. It is however good enough for who it is for and serves the purpose nicely. I plan to continue on the same path. Everything shown and utilized is owned and operated by me, myself, and I, so feel no need to apologize for the ways I get things accomplished. Thanks for your input as it is appreciated but will not be required in the future.
The problem on a forum is other people might tend to copy what someone else did without realizing the risks if something goes wrong. I was just trying to give a safer option. I kind of feel it's important for me or someone else to point out potential issues with using the wrong welding techniques. I'm sure you'd feel terrible if someone copied your procedures and got injured because it failed. I've always tried to stress there's a reason for the different welding rods, wire's, welding processes and welding procedures. Something that could come crashing down if it fails gets my attention.
I'm straight enough that if this repair were to fail, it will be posted, but it's not going to; hence the reasoning behind anybody seeing it in process. Done this kind of work too long to not be confident of my abilities and certainly have no reliance upon internet "credibility" for status or anything of the sort. Whether this repair goes as planned or fails miserably, has no impact upon you Dave. I could be very incorrect but I don't think there is a fool in the world that would trust an E6011 electrode pushed with a 20% duty cycle AC only welder and place their life in jeopardy under such heavy weldments, but you bit and ran with the story readily. This was only done to rile you up which was intended to be humorous. I thought hard on the E6013 idea but that would be plagarizing from another party. You then find the impudence to berate and question the procedures that actually took place which has always been planned to be posted. Knowing you are a bit "touchy" to such activity the purpose was to bring a little humor to the thread. I am truly sorry you took offense as it was not meant that way in any fashion. Being proud is one thing, but going on the attack because you don't agree with something is totally different. Good night Dave. Take a couple of pills and sleep well. Hopefully you awaken to a better day tomorrow. I authorize the moderation team to delete this thread in it's entirety without delay if desired. I have no ill will or negative thoughts on it but the conclusion of the project will be kept private till completion, or failure. Not a lot of sense posting things of no interest except negativity to others would be my thoughts. Thanks,
How come you didn't just wrap an sling around the boom?
Technically if the boom lift was used commercially welding on the boom would be illegal unless engineer approved and done by a qualified welder. Your attempt at humor on my behalf failed. It wouldn't be very funny if someone else did something similar using the wrong welding procedure and it failed. That's why I posted there's a better procedure. I also mentioned wrapping a sling around it.
I'd clap, but I'm holding two fresh cartons of hot popcorn . . .